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The commercial mature gallium nitride high electron mobility transistors (GaN HEMT) technology has drawn much attention for its great potential in industrial power electronic applications. GaN HEMT is known for low on-state resistance, high withstand voltage, and high switching frequency. This paper presents comparative experimental evaluations of GaN HEMT and conventional Si insulated gate bipolar transistors (Si IGBTs) of similar power rating. The comparative study is carried out on both the element and converter level. Firstly, on the discrete element level, the steady and dynamic characteristics of GaN HEMT are compared with Si-IGBT, including forward and reverse conducting character, and switching time. Then, the elemental switching losses are analyzed based on measured data. Finally, on a complementary buck converter level, the overall efficiency and EMI-related common-mode currents are compared. For the tested conditions, it is found that the GaN HEMT switching loss is much less than for the same power class IGBT. However, it is worth noting that special attention should be paid to reverse conduction losses in the PWM dead time (or dead band) of complementary-modulated converter legs. When migrating from IGBT to GaN, choosing a dead-time and negative gate drive voltage in conventional IGBT manner can make GaN reverse conducting losses high. It is suggested to use 0 V turn-off gate voltage and minimize the GaN dead time in order to make full use of the GaN advantages.

Blood-pool agents (BPAs) are MRI contrast agents (CAs) characterized by their long circulation in the vascular system to provide an extended time window for high-resolution MR angiography (MRA). Prolonged vascular retention, however, impedes the excretion of BPAs. Therefore, chemical strategy to regulate the balance between retention and clearance is important to reach optimal pharmacokinetics. We recently developed MnP2, the first Mn(III)-porphyrin (MnP) based BPA. MnP2 shows high T1 relaxivity (r1) and high affinity to human serum albumin (HSA) that leads to up to 48-h vascular retention in rats. However, upon albumin binding, the r1 is decreased. To modulate vascular retention time and plasma r1, a regioisomer of MnP2, m-MnP2, was synthesized. The free m-MnP2 exhibits lower r1 than that of MnP2 at magnetic fields above 2 MHz, which agrees with their relative hydrodynamic sizes. The HSA binding of m-MnP2 was evaluated using UV-Vis spectroscopy and found to have tuned-down affinity in comparison with MnP2. Upon HSA binding, the protein complex of m-MnP2 exhibits an r1 of 11.8 mM−1 s−1 at 3 T, which is higher than that of MnP2 bound to HSA. Taken together, this demonstrated the role of molecular geometry in optimizing the pharmacokinetics of albumin-targeting BPAs.

Integrated assessment models and coupled earth system models both have their limitations in understanding the interactions between human activity and the physical earth system. In this paper, a new human--earth system model, BNU- HESM1.0, constructed by combining the economic and climate damage components of the Dynamic Integrated Model of Climate Change and Economy to the BNU-ESM model, is introduced. The ability of BNU-HESM1.0 in simulating the global CO2 concentration and surface temperature is also evaluated. We find that, compared to observation, BNU-HESM1.0 underestimates the global CO2 concentration and its rising trend during 1965-2005, due to the uncertainty in the economic components. However, the surface temperature simulated by BNU-HESM1.0 is much closer to observation, resulting from the overestimates of surface temperature by the original BNU-ESM model. The uncertainty of BNU-ESM falls within the range of present earth system uncertainty, so it is the economic and climate damage component of BNU-HESM 1.0 that needs to be improved through further study. However, the main purpose of this paper is to introduce a new approach to investigate the complex relationship between human activity and the earth system. It is hoped that it will inspire further ideas that prove valuable in guiding human activities appropriate for a sustainable future climate.

Based on observations and 12 simulations from Coupled Model Intercomparison Project Phase 5 （CMIP5） models, cli- matic extremes and their changes over China in the past and under the future scenarios of three Representative Concentration Pathways （RCPs） are analyzed. In observations, frost days （FD） and low-temperature threshold days （TN10P） show a de- creasing trend, and summer days （SU）, high-temperature threshold days （TX90P）, heavy precipitation days （R20）, and the contribution of heavy precipitation days （P95T） show an increasing trend. Most models are able to simulate the main char- acteristics of most extreme indices. In particular, the mean FD and TX90P are reproduced the best, and the basic trends of FD, TN10P, SU and TX90P are represented. For the FD and SU indexes, most models show good ability in capturing the spatial differences between the mean state of the periods 1986--2005 and 1961-80; however, for other indices, the simulation abilities for spatial disparity are less satisfactory and need to be improved. Under the high emissions scenario of RCP8.5, the century-scale linear changes of the multi-model ensemble （MME） for FD, SU, TN10P, TX90P, R20 and P95T are -46.9, 46.0, -27.1, 175.4, and 2.9 days, and 9.9%, respectively; and the spatial change scope for each index is consistent with the emissions intensity. Due to the complexities of physical process pararneterizations and the limitation of forcing data, great uncertainty still exists with respect to the simulation of climatic extremes.

Thermoelectric technology has recently emerged as a distinct therapeutic modality. However, its therapeutic effectiveness is significantly limited by the restricted temperature gradient within living organisms. In this study, we introduce a high-performance plasmonic-thermoelectric catalytic therapy utilizing urchin-like Cu 2−x Se hollow nanospheres (HNSs) with a cascade of plasmonic photothermal and thermoelectric conversion processes. Under irradiation by a 1064 nm laser, the plasmonic absorption of Cu 2−x Se HNSs, featuring rich copper vacancies (V Cu ), leads to a rapid localized temperature gradient due to their exceptionally high photothermal conversion efficiency (67.0%). This temperature gradient activates thermoelectric catalysis, generating toxic reactive oxygen species (ROS) targeted at cancer cells. Density functional theory calculations reveal that this vacancy-enhanced thermoelectric catalytic effect arises from a much more carrier concentration and higher electrical conductivity. Furthermore, the exceptional photothermal performance of Cu 2−x Se HNSs enhances their peroxidase-like and catalase-like activities, resulting in increased ROS production and apoptosis induction in cancer cells. Here we show that the accumulation of copper ions within cancer cells triggers cuproptosis through toxic mitochondrial protein aggregation, creating a synergistic therapeutic effect. Tumor-bearing female BALB/c mice are used to evaluate the high anti-cancer efficiency. This innovative approach represents the promising instance of plasmonic-thermoelectric catalytic therapy, employing dual pathways (membrane potential reduction and thioctylated protein aggregation) of mitochondrial dysfunction, all achieved within a singular nanostructure. These findings hold significant promise for inspiring the development of energy-converting nanomedicines. Thermoelectric catalytic therapy is an emerging therapeutic approach but faces the issue of limited temperature variations in living organisms. Here the authors address this issue by developing urchin-like Cu 2−x Se hollow nanospheres that display a cascade of plasmonic photothermal and thermoelectric conversion processes for plasmonic-thermoelectric catalytic cancer therapy.

HighlightsClassification and catalytic mechanism of nanozymes with different mimicking activities are dissertated.Activity prediction and rational design methods of nanozymes are highlighted, including density functional theory, machine learning, biomimetic and chemical design.The roles of nanozymes in different synergistic theranostic strategies for tumor are summarized and explained by representative examples in the past five years.Since the discovery of enzyme-like activity of Fe3O4 nanoparticles in 2007, nanozymes are becoming the promising substitutes for natural enzymes due to their advantages of high catalytic activity, low cost, mild reaction conditions, good stability, and suitable for large-scale production. Recently, with the cross fusion of nanomedicine and nanocatalysis, nanozyme-based theranostic strategies attract great attention, since the enzymatic reactions can be triggered in the tumor microenvironment to achieve good curative effect with substrate specificity and low side effects. Thus, various nanozymes have been developed and used for tumor therapy. In this review, more than 270 research articles are discussed systematically to present progress in the past five years. First, the discovery and development of nanozymes are summarized. Second, classification and catalytic mechanism of nanozymes are discussed. Third, activity prediction and rational design of nanozymes are focused by highlighting the methods of density functional theory, machine learning, biomimetic and chemical design. Then, synergistic theranostic strategy of nanozymes are introduced. Finally, current challenges and future prospects of nanozymes used for tumor theranostic are outlined, including selectivity, biosafety, repeatability and stability, in-depth catalytic mechanism, predicting and evaluating activities.

Peripheral T-cell lymphoma (PTCL) is a rare and heterogeneous group of hematological malignancies. Compared to our knowledge of B-cell tumors, our understanding of T-cell leukemia and lymphoma remains less advanced, and a significant number of patients are diagnosed with advanced stages of the disease. Unfortunately, the development of drug resistance in tumors leads to relapsed or refractory peripheral T-Cell Lymphomas (r/r PTCL), resulting in highly unsatisfactory treatment outcomes for these patients. This review provides an overview of potential mechanisms contributing to PTCL treatment resistance, encompassing aspects such as tumor heterogeneity, tumor microenvironment, and abnormal signaling pathways in PTCL development. The existing drugs aimed at overcoming PTCL resistance and their potential resistance mechanisms are also discussed. Furthermore, a summary of ongoing clinical trials related to PTCL is presented, with the aim of aiding clinicians in making informed treatment decisions.

为研究有机肥替代化肥比例对青稞产量、养分利用和土壤性质的影响，本研究以“昆仑14号”青稞为供试材料，设置7个试验处理，分别为不施肥（CK）、常规施肥（CF）以及有机肥替代20%（T1）、40%（T2）、60%（T3）、80%（T4）、100%（T5），研究等养分投入下有机肥替代比例对青稞产量、干物质积累量、养分积累量、肥料利用率、土壤理化性质和酶活性的影响。结果表明：随有机肥替代比例增加，青稞产量、干物质积累量、养分积累量和肥料利用率呈逐渐降低趋势，与CF相比，T1处理能显著提高青稞产量、养分积累量和肥料利用率；有机肥替代处理较CF提高了土壤有机质和硝态氮含量，降低了土壤pH值和铵态氮含量，对土壤全氮含量无显著影响，T1处理较CF提高了土壤速效磷和速效钾含量；有机肥替代处理土壤酶活性较CF处理明显提高，T1~T3处理脲酶活性显著提高15.76%~19.51%，有机肥替代处理土壤碱性磷酸酶活性显著提高24.32%~34.25%，T1和T3处理更有利于土壤酶活性的提高。运用主成分分析法对各处理进行综合性评价，得分排序为T1>CF>T2>T3>T4>T5>CK。研究表明，有机肥替代化肥可改善土壤理化性质，提高土壤酶活性，适宜比例的有机肥替代较常规施肥促进了青稞吸收利用养分并提高了产量，从综合性评分结果来看，有机肥替代20%处理效果最佳，为推荐施肥模式。

Largemouth bass (Micropterus salmoides) is an important aquaculture species increasingly threatened by viral diseases, particularly largemouth bass virus (LMBV), which can cause significant mortality. However, integrative analyses linking LMBV-induced gut microbiota dysbiosis to metabolomic dysfunction are limited. In this study, we profiled the intestinal microbiome and metabolome alterations in largemouth bass following LMBV infection and conducted an integrated analysis. Infected fish showed reduced alpha diversity and significant shifts in community structure, including increased relative abundances of Bacteroidota and Fusobacteriota and a decrease in Proteobacteria. Opportunistic taxa, such as Pseudomonas and Mycobacterium, were enriched after infection. Metabolomic profiling revealed differential metabolites primarily involved in amino acid and carbohydrate metabolism. Integrative correlation analyses further identified significant associations between opportunistic bacteria and putative harmful metabolites, suggesting that LMBV-induced dysbiosis disrupts host metabolic homeostasis and contributes to immune dysfunction. These findings may clarify the microbiota–metabolite landscape during LMBV infection.

Superconducting diodes, characterized by the nonreciprocal supercurrent flow, have gained significant attention for their potential in dissipationless electronics. This study presents a superconducting quantum interference device (SQUID) composed of two Al-InSb nanosheet Josephson junctions. Utilizing prepatterned local backgates, we achieve a gate- and flux-tunable superconducting diode with controllable efficiency in both amplitude and sign. Numerical simulations attribute the diode effect to higher harmonics in the current-phase relation. Crucially, fractional Shapiro step experiments provide direct insights into the evolution of these higher harmonics with flux tuning, showcasing significant enhancements in the second-harmonic signatures of the SQUID near half-integer flux quanta. Furthermore, we investigate the microwave-assisted diode response and experimentally show that the polarity of the diode effect can be switched by the microwave power. These results demonstrate the potential of InSb nanosheet-based hybrid devices as highly tunable elements for use in dissipationless electronics.