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Most existing methods for visual domain adaptation need to convert high-order tensors into one-order high-dimensional vectors through naive vectorization operations. However, they not only destroy the internal spatial structure within the original high-order tensors, but also result in exponentially increasing model parameters. To address these problems, we propose a novel method for visual domain adaptation by representing tensorial features in tensor-train subspace in this paper. Specifically, we firstly provide a theoretical deduction by constructing a tensor-train subspace and proving its linearity and left-orthogonality. Secondly, to extract common tensorial features between source and target domains, we formulate the visual domain adaptation problem into an optimization problem that models the aforementioned common tensor-train subspace between two domains, as well as their corresponding projections. Thirdly, we design a tensor-train subspace representation algorithm (TTSR) to solve the multiple variables optimization problem by optimizing its sub-problems iteratively, so as to process high-order tensorial features. Finally, we evaluate the performance of our proposed TTSR algorithm by conducting extensive experiments on three popular public datasets. The experimental results demonstrate that the TTSR algorithm can improve the classification accuracy of unlabeled target domain than that of baseline algorithms.

Lethal lipid peroxidation caused by reactive oxygen species occurs in different types of programmed cell death, especially in ferroptosis. Ferroptosis inducers, which serve as small-molecule probes, can provide insight into the mechanism of ferroptosis and facilitate drug discovery. The classical ferroptosis inducers indirectly lead to lipid peroxidation; thus, it is difficult to explore lipid regulation during the ferroptotic process. In this study, we designed two quinazolinone-based lipophilic probes BODIQPy-TPAand QPy-TPA, which proved to directly induce lipid peroxidation by light irradiation in vitro. The probe BODIQPy-TPA, which was mainly distributed in the endoplasmic reticulum (ER), specifically triggered ferroptosis in B16 and HepG2 cells upon light irradiation. As a comparison, the probe QPy-TPA, which was mainly distributed in lipid droplets (LDs), induced cell death by a nonferroptotic pathway. Further lipidomic analysis revealed that these two probes caused different patterns of lipid regulation and lipid peroxidation, suggesting that ferroptosis might activate distinct lipid regulation.

With the continuous advancement of Industry 4.0 and intelligent manufacturing, remaining useful lifetime (RUL) prediction can forecast the future degradation state of machinery and then estimate the remaining service time before it loses its safe operation ability. Accordingly, a series of predictive maintenance strategies can be regulated in advance for equipment in the Industrial Internet of Things. To tackle the challenges of insufficiency of failure data and lack of confidence in RUL prediction results, a similarity-based relevance vector machine (SRVM) is proposed in this article. Primarily, the relationship among latent variables in the SRVM is learned adaptively through similarity computations to fully utilize the limited degradation data. Furthermore, these internal variables in the SRVM are treated as time-varying variables and re-estimated dynamically to provide RUL prediction with reliable confidence. The experiment results show that the prediction accuracy of the SRVM is higher than that of other baseline methods.

The design of soft robots capable of navigation underwater has received tremendous research interest due to the robots’ versatile applications in marine explorations. Inspired by marine animals such as jellyfish, scientists have developed various soft robotic fishes by using elastomers as the major material. However, elastomers have a hydrophobic network without embedded water, which is different from the gel-state body of the prototypes and results in high contrast to the surrounding environment and thus poor acoustic stealth. Here, we demonstrate a manta ray-inspired soft robot fish with tailored swimming motions by using tough and stiff hydrogels as the structural elements, as well as a dielectric elastomer as the actuating unit. The switching between actuated and relaxed states of this unit under wired power leads to the flapping of the pectoral fins and swimming of the gel fish. This robot fish has good stability and swims with a fast speed (∼10 cm/s) in freshwater and seawater over a wide temperature range (4–50 °C). The high water content (i.e., ∼70 wt %) of the robot fish affords good optical and acoustic stealth properties under water. The excellent mechanical properties of the gels also enable easy integration of other functional units/systems with the robot fish. As proof-of-concept examples, a temperature sensing system and a soft gripper are assembled, allowing the robot fish to monitor the local temperature, raise warning signals by lighting, and grab and transport an object on demand. Such a robot fish should find applications in environmental detection and execution tasks under water. This work should also be informative for the design of other soft actuators and robots with tough hydrogels as the building blocks.

Targeted prodrug strategy, which utilizes the endogenous biomarkers in cancer cells as activators to release the active drug, has been well established either in the fundamental research or the clinical treatment. However, many prodrugs suffer from safety concern due to “off-target activation”. Dual or multiple biomarkers triggered prodrug may provide an effective strategy to overcoming the “off-target effect”. Melanoma cells have both high levels of reactive oxygen species(ROS) and tyrosinase(TYR), which makes them significantly different from other tumor cells and normal cells. Here we reported a series of quinazolinone-aryl boronic acid/ester-based prodrugs, which can be activated by the cascade of ROS and TYR and selectively kill melanoma cells. The structure-activity relationship(SAR) analysis revealed that mitochondria-targeting property was vital for their cytotoxicity and the dual activated effector played a significant role in their selectivity towards melanoma cells. Among these candidates, compound 4b showed the highest toxicity to B16, leading to an imbalance of the redox system in melanoma cells, causing mitochondrial DNA damage, and then promoting melanoma cells death.

Fluorogenic organic materials have gained tremendous attention due to their unique properties. However, only a few of them are suitable for bioimaging. Their different behaviors in organic and cellular environments hinder their application in bioimaging. Thus understanding the photoluminescent behaviors of organic materials in a cellular context is particularly important for their rational design. Herein, we describe two coumarin-quinazolinone conjugates: CQand MeCQ. The high structure similarity makes them possess similar physical and photophysical properties, including bright fluorescence ascribed to the monomer forms in organic solvents and aggregation-caused quenching (ACQ) effect due to self-assembly aggregation in aqueous solution. However, they behave quite differently in cellular context: that is, CQexhibits bright fluorescence in living cells, while the fluorescence of MeCQis almost undetectable. The different performance between CQand MeCQin living cells is attributed to their different scenario in G-quadruplex (G4) DNA interaction. CQselectively binds with G4 DNA to recover its fluorescence viaaggregation–disaggregation switching in living cells, while MeCQremained in the aggregate form due to its poor interplay with G4 DNA. Furthermore, CQis applied as a two-photon fluorescent dye, and its photoswitchable fluorescence capability is exploited for super-resolution imaging of the specific mitochondrial structure in living cells viathe STORM technique.

The deep sea remains the largest unknown territory on Earth because it is so difficult to explore1–4. Owing to the extremely high pressure in the deep sea, rigid vessels5–7and pressure-compensation systems8–10are typically required to protect mechatronic systems. However, deep-sea creatures that lack bulky or heavy pressure-tolerant systems can thrive at extreme depths11–17. Here, inspired by the structure of a deep-sea snailfish15, we develop an untethered soft robot for deep-sea exploration, with onboard power, control and actuation protected from pressure by integrating electronics in a silicone matrix. This self-powered robot eliminates the requirement for any rigid vessel. To reduce shear stress at the interfaces between electronic components, we decentralize the electronics by increasing the distance between components or separating them from the printed circuit board. Careful design of the dielectric elastomer material used for the robot’s flapping fins allowed the robot to be actuated successfully in a field test in the Mariana Trench down to a depth of 10,900 metres and to swim freely in the South China Sea at a depth of 3,224 metres. We validate the pressure resilience of the electronic components and soft actuators through systematic experiments and theoretical analyses. Our work highlights the potential of designing soft, lightweight devices for use in extreme conditions.

AbstractCastor (Ricinus communisL.) is one of the world's top ten oil crops. China is the second largest producer of castor beans, but China's castor bean acreage has been declining. A principal reason for this decline is the prevalence of weeds and the absence of herbicide resistant varieties of castor plants. In this study, we used Agrobacterium-mediated gene transfer to introduce the EPSPS(5-enolpyruvylshikimate-3-phosphate synthase) gene, which confers resistance to glyphosate, and the Bar(phosphinothricin N-acetyltransferase) gene, encoding resistance to glufosinate, into castor 2129 (high stem excellent recovery line) and CSR 181 (dwarf stem excellent recovery line). The transgenic plants exhibited significantly increased expression of the EPSPSand Bargenes and significantly increased resistance to glyphosate and glufosinate. Proteomic analysis showed differences in the amounts of 20 proteins in the dwarf stem transgenic plants. Nine of these proteins are involved in photosynthesis and indirectly related to the mechanism of action of the Bargene. Eight proteins are involved in defense, repair, stress response, oxidative phosphorylation, and metabolic pathways and are indirectly related to the mechanism of action of the EPSPSgene. These results provide a foundation for the preparation of high herbicide resistant castor varieties.

Cancer immunotherapy can enhance the antitumor effect of drugs through a combinatorial approach in a synergistic manner. However, the effective targeted delivery of various drugs remains a challenge. We generated a peptide assembling tumor-targeted nanodelivery system based on a breast cancer homing and penetrating peptide for the codelivery of a programmed cell death ligand 1 (PD-L1) small interfering RNA (siRNA) (siPD-L1) and an indoleamine 2,3-dioxygenase inhibitor as a dual blockade of an immune checkpoint. The vector is capable of specifically accumulating in the breast cancer tumor site in a way that allows the siRNA to escape from endosomal vesicles after being endocytosed by tumor cells. The drug within these cells then acts to block tryptophan metabolism. The results showed that locally released siPD-L1 and 1-methyl-dl-tryptophan favor the survival and activation of cytotoxic T lymphocytes, resulting in apoptosis of breast cancer cells. Therefore, this study provides a potential approach for treating breast cancer by blocking immunological checkpoints through the assembly of micelles with functional peptides.

The paper proposes a novel matrix completion algorithm for data collection in wireless sensor networks through incorporating a randomised version of Kaczmarz method. By splitting the matrix completion problem into two convex sub-problems and solving the optimal probability computing problem in the randomised Kaczmarz method approximately with the D-optimal design solution, we reduce the reconstruction error and accelerate the convergence speed of the matrix completion computation. The synthetic data experiments show that the proposed algorithm presents more accurate reconstruction accuracy and faster reconstruction speed than the state-of-the-art matrix completion algorithms. Furthermore, we verify the practicality of the proposed matrix completion algorithm in real data collection scenario of wireless sensor networks through the experiments based on the real sensed dataset.

Lithium ion batteries with Li-rich cathodes is attracting tremendous attention due to its high specific capacity but it also suffers from the undesirable cyclic performance due to the oxygen release and irreversible lithium loss in initial cycle. To offset the tough question of initial lithium loss caused by the formation of SEI, lithium oxide was applied as the extra lithium sources and stabilize agent of Li1.15Ni0.17Co0.11Mn0.57O2, and it is found that a proper amount of lithium oxide can improve the initial charge and discharge capacity. Compared with raw materials, the initial charge and discharge capacity of lithium-rich materials with 6wt% lithium oxide increased by 5% and 6.4%, respectively. The composited cathodes show improved rate capacity and cyclic stability. It was found that the addition of a small amount of lithium oxide did not change the charge and discharge reaction process rather made the oxidation peaks move slightly to the direction of low potential. It was also conducive to the realization of higher capacity and improved the migration of lithium ions gradually after cycling. The reduction of impedance after adding Li2O in Li1.15Ni0.17Co0.11Mn0.57O2 may be the main reason for the improvement of electrochemical performance.

AbstractRicinoleic acid, one of the biggest components in castor oil, is an unusual fatty acid with numerous industrial applications. Despite much research on the oil content of Ricinus communisL., the genes encoding the oil biosynthesis function in the seed developmental stages are still poorly known. Here, we analyzed differentially expressed transcripts during seed development using cDNA-amplified fragment length polymorphism. Almost all ingredients significantly decreased along with seed maturation, except for ricinoleic acid, which increased greatly from 6.7% to 86.8%. A total of 534 distinguished fragments were differentially expressed in six development stages. Among these, 67 fragments showed high homology with known-function genes, and 26 sequences were successfully annotated with fatty acid synthesis or storage proteins in castor and other species. The results showed that fatty acid synthesis and accumulation in castor seeds displayed various temporal patterns. Different cDNA-fragment patterns were mainly found in later development stages, coinciding with the onset of oil synthesis.

ABSTRACTDNA methylation plays an important role in endosperm development and is involved in the epigenetic regulation of gene expression. However, the epigenetic regulation of castor seed development has not yet been reported. In this study, methylation-sensitive amplification polymorphism (MSAP) analysis was used to investigate the methylation level in castor. In 20-day-old castor seeds, 41.17% of the fragments were fully methylated and 15.61% were hemimethylated. In 60 day-old seed, the full methylation and hemimethylation rates were 19.77% and 7.56%, respectively, suggesting that some methylation level changes existed during the castor seed development. A total of 647 bands were identified with different methylation or demethylation patterns during the seed maturation. However, only 37 sequences were homologous to well-known proteins, such as phospholipid-transporting ATPase, phosphatases and methyltransferase. Therefore, these results clearly demonstrated that the MSAP technique is very useful for the analysis of the global DNA methylation state in castor and the complexity of DNA methylation changes during seed development. The different methylation levels may be correlated with the specific gene expression in different seed development stages.

This paper focuses on selecting the appropriate filtering location to minimize the amount of filtering routers in the traceback-based packet filtering for defending against the large-scale Bandwidth denial-of-service (BDoS) attacks. The filtering location can be viewed as a resource allocation problem and further we formulate it to an integer linear programming model and design an exact and computationally efficient filtering location algorithm. The evaluation results show that our algorithm brings significant benefits in practice.

Protein S-sulfenylation (protein sulfenic acid), as one of the most significant oxidative post-translational modifications (OxiPTMs), plays a vital role in regulating protein function. A variety of activity-based probes have been developed to profile sulfenic acid in living cells. However, due to the transient presence and low content of sulfenic acid in living cell, high doses of probes are needed to achieve efficient labeling. More importantly, current probes have no temporal control over sulfenic acid labeling. To overcome these limitations, two caged cysteine sulfenic acid probes DYn-2-ONB and DYn-2-Cou with either an o-nitrobenzyl or coumarin protecting group were developed in this study. Both probes can be efficiently uncaged viairradiation to produce the active C-nucleophile probe DYn-2. Labeling assay in living cells demonstrated DYn-2-ONB exhibited better labeling capacity compared with DYn-2, providing it as a powerful tool for improved monitoring of protein S-sulfenylation in living cells.

Small-molecule-based fluorescent chemosensors provide powerful tools for analytical chemistry. However, their organic essence often “cursed” them for aggregation-caused quenching (ACQ) in an aqueous context. Albeit the praxis of the disaggregation-induced emission (DIE) strategy as a potential solution, it still awaited improvement due to the uncontrollability of the aggregation/segregation process. To address this issue, herein, we supposed that sulfur substitution on a molecule could serve as a promising strategy to achieve an evolved ACQ-DIE probe. To prove this concept, a precursor G-quadruplex (G4) ligand CQwas modified to get its thionation version CTQ. Strikingly, CTQexhibited more arranged aqueous segregation behavior, as compared with CQ, and therefore enhanced fluorescence performance. Our research, in the meantime, manifested that CTQremained to possess favorable G4 selectivity, whereby it could function as an evolved probe for more accurate in vitro G4-related assays, specifically, a classification assay for distinguishing virus variants.

Activity-based near-infrared (NIR) fluorescent probes provide powerful tools for diagnosis of diseases. However, most of these probes suffer from low specificity due to “off-target” reaction. The dual-locked strategy, which utilizes two biomarkers as triggers, can increase the specificity and precision of diagnosis. Here, we report a dual-locked NIR probe, MB-m-borate, which releases fluorophore methylene blue (MB) after hydrogen peroxide–tyrosinase (H2O2-TYR) cascade activation. Both MB-m-borateand its intermediate MB-m-phenol(the product after H2O2activation) show almost nondetectable fluorescence. MB-m-borateexhibits “turn on” fluorescence upon H2O2-TYR cascade activation. The further live cell bioimaging results indicate that MB-m-borateonly responds to melanoma cells, providing it as a robust probe for precise detection of melanoma. Finally, the probe is applied for the diagnosis of melanoma in vivo with a xenogeneic mouse model.

Lithium ion batteries with Li-rich cathodes is attracting tremendous attention due to its high specific capacity but it also suffers from the undesirable cyclic performance due to the oxygen release and irreversible lithium loss in initial cycle. To offset the tough question of initial lithium loss caused by the formation of SEI, lithium oxide was applied as the extra lithium sources and stabilize agent of Li1.15Ni0.17Co0.11Mn0.57O2, and it is found that a proper amount of lithium oxide can improve the initial charge and discharge capacity. Compared with raw materials, the initial charge and discharge capacity of lithium-rich materials with 6wt% lithium oxide increased by 5% and 6.4%, respectively. The composited cathodes show improved rate capacity and cyclic stability. It was found that the addition of a small amount of lithium oxide did not change the charge and discharge reaction process rather made the oxidation peaks move slightly to the direction of low potential. It was also conducive to the realization of higher capacity and improved the migration of lithium ions gradually after cycling. The reduction of impedance after adding Li2O in Li1.15Ni0.17Co0.11Mn0.57O2may be the main reason for the improvement of electrochemical performance.

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