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Magnetic resonance imaging (MRI) is a non-invasive imaging technology to diagnose health conditions, showing the weakness of low sensitivity. Herein, we synthesize a contrast agent, SPIO@SiO 2 @MnO 2 , which shows decreased T 1 and T 2 contrast intensity in normal physiological conditions. In the acid environment of tumor or inflamed tissue, the manganese dioxide (MnO 2 ) layer decomposes into magnetically active Mn 2+ (T 1 -weighted), and the T 1 and T 2 signals are sequentially recovered. In addition, both constrast quenching-activation degrees of T 1 and T 2 images can be accurately regulated by the silicon dioxide (SiO 2 ) intermediate layer between superparamagnetic iron oxide (SPIO) and MnO 2 . Through the “dual-contrast enhanced subtraction” imaging processing technique, the contrast sensitivity of this MRI contrast agent is enhanced to a 12.3-time difference between diseased and normal tissue. Consequently, SPIO@SiO 2 @MnO 2 is successfully applied to trace the tiny liver metastases of approximately 0.5 mm and monitor tissue inflammation. Magnetic resonance imaging (MRI) is a well-established non-invasive medical imaging technology. Here, to improve the performance of the technique, the authors describe the design of a pH-responsive T1-T2 dual-modal MRI contrast agent, showing enhanced imaging sensitivity in preclinical cancer models.

The comprehensive understanding and proper use of supramolecular interactions have become critical for the development of functional materials, and so is the biomedical application of nucleic acids (NAs). Relatively rare attention has been paid to hydrophobic interaction compared with hydrogen bonding and electrostatic interaction of NAs. However, hydrophobic interaction shows some unique properties, such as high tunability for application interest, minimal effect on NA functionality, and sensitivity to external stimuli. Therefore, the widespread use of hydrophobic interaction has promoted the evolution of NA‐based biomaterials in higher‐order self‐assembly, drug/gene‐delivery systems, and stimuli‐responsive systems. Herein, the recent progress of NA‐based biomaterials whose fabrications or properties are highly determined by hydrophobic interactions is summarized. 1) The hydrophobic interaction of NA itself comes from the accumulation of base‐stacking forces, by which the NAs with certain base compositions and chain lengths show properties similar to thermal‐responsive polymers. 2) In conjugation with hydrophobic molecules, NA amphiphiles show interesting self‐assembly structures with unique properties in many new biosensing and therapeutic strategies. 3) The working‐mechanisms of some NA‐based complex materials are also dependent on hydrophobic interactions. Moreover, in recent attempts, NA amphiphiles have been applied in organizing macroscopic self‐assembly of DNA origami and controlling the cell–cell interactions. Herein, recent advances in nucleic acid‐based biomaterials whose fabrications or properties are highly dependent on hydrophobic interactions are summarized. Such biomaterials exhibit emerging properties, such as diversified functionalities, more sensitive stimuli‐responsiveness, and hierarchical self‐assembly capability, which determines that hydrophobic interaction will become a potent tool in the design of nucleic acid‐based biomaterials in the future.

Practical photodynamic therapy calls for high-performance, less O 2 -dependent, long-wavelength-light-activated photosensitizers to suit the hypoxic tumor microenvironment. Iridium-based photosensitizers exhibit excellent photocatalytic performance, but the in vivo applications are hindered by conventional O 2 -dependent Type-II photochemistry and poor absorption. Here we show a general metallopolymerization strategy for engineering iridium complexes exhibiting Type-I photochemistry and enhancing absorption intensity in the blue to near-infrared region. Reactive oxygen species generation of metallopolymer Ir-P1 , where the iridium atom is covalently coupled to the polymer backbone, is over 80 times higher than that of its mother polymer without iridium under 680 nm irradiation. This strategy also works effectively when the iridium atom is directly included ( Ir-P2 ) in the polymer backbones, exhibiting wide generality. The metallopolymer nanoparticles exhibiting efficient O 2 •− generation are conjugated with integrin αvβ3 binding cRGD to achieve targeted photodynamic therapy. Iridium-based photosensitizers exhibit good photocatalytic performance, but the in vivo applications are hindered by conventional O 2 -dependent Type-II photochemistry and poor absorption. Here, the authors report a general metallopolymerization strategy for engineering iridium complexes exhibiting Type-I photochemistry and enhancing absorption intensity in the blue to near-infrared region.

Recent investigations reveal that lactate is not a waste product but a major energy source for cells, especially in the mitochondria, which can support cellular survival under glucose shortage. Accordingly, the new understanding of lactate prompts to target it together with glucose to pursue a more efficient cancer starvation therapy. Herein, zeolitic imidazolate framework‐8 (ZIF‐8) nanoplatforms are used to co‐deliver α‐cyano‐4‐hydroxycinnamate (CHC) and glucose oxidase (GOx) and fulfill the task of simultaneous depriving of lactate and glucose, resulting in a new nanomedicine CHC/GOx@ZIF‐8. The synthesis conditions are carefully optimized in order to yield monodisperse and uniform nanomedicines, which will ensure reliable and steady therapeutic properties. Compared with the strategies aiming at a single carbon source, improved starvation therapy efficacy is observed. Besides, more than boosting the energy shortage, CHC/GOx@ZIF‐8 can block the lactate‐fueled respiration and relieve solid tumor hypoxia, which will enhance GOx catalysis activity, depleting extra glucose, and producing more cytotoxic H2O2. By the synergistically enhanced anti‐tumor effect, both in vitro and in vivo cancer‐killing efficacies of CHC/GOx@ZIF‐8 show twice enhancements than the GOx mediated therapy. The results demonstrate that the dual‐depriving of lactate and glucose is a more advanced strategy for strengthening cancer starvation therapy. Metal‐organic‐framework nanomedicines encapsulating an inhibitor of monocarboxylate transporters 1 and glucose oxidase are developed for efficient glucose depletion while inhibiting the lactate influx. At meanwhile, inhibiting the lactate influx can improve the intracellular oxygen pressure, which subsequently promotes the catalytic activity of glucose oxidase. Cancer cells are substantially killed from ATP shortage and high ROS levels.

Background Removal of heavy metals from water and soil is a pressing challenge in environmental engineering, and biosorption by microorganisms is considered as one of the most cost-effective methods. In this study, the metal-binding proteins MerR and ChrB derived from Cupriavidus metallidurans were separately expressed in Escherichia coli BL21 to construct adsorption strains. To improve the adsorption performance, surface display and codon optimization were carried out. Results In this study, we constructed 24 adsorption engineering strains for Hg 2+ and Cr 6+ , utilizing different strategies. Among these engineering strains, the M’-002 and B-008 had the strongest heavy metal ion absorption ability. The M’-002 used the flexible linker and INPN to display the merR opt at the surface of the E. coli BL21, whose maximal adsorption capacity reached 658.40 μmol/g cell dry weight under concentrations of 300 μM Hg 2+ . And the B-008 overexpressed the chrB in the intracellular, its maximal capacity was 46.84 μmol/g cell dry weight under concentrations 500 μM Cr 6+ . While in the case of mixed ions solution (including Pb 2+ , Cd 2+ , Cr 6+ and Hg 2+ ), the total amount of ions adsorbed by M’-002 and B-008 showed an increase of up to 1.14- and 4.09-folds, compared to the capacities in the single ion solution. Conclusion The construction and optimization of heavy metal adsorption strains were carried out in this work. A comparison of the adsorption behavior between single bacteria and mixed bacteria systems was investigated in both a single ion and a mixed ion environment. The Hg 2+ absorption capacity is reached the highest reported to date with the engineered strain M’-002, which displayed the merR opt at the surface of chassis cell, indicating the strain’s potential for its application in practical environments.

With the rapid growth of global demand for water and energy, the two increasingly restrict economic and social development. The total energy consumption and water use are positively correlated. Identifying the key drivers influencing the energy-water development can realize national resource management and sustainable supplement. In this context, this study aims to capture the key driving forces that affect the sustainable energy-water development characteristics in Chinese change processes throughout 2000–2017. Five driving forces, the EW intensity effect, industrial structure effect, GDP value-added effect, income improvement effect, and population-scale effect, were further decomposed by the logarithmic mean Divisia index (LMDI) model to explore the energy consumption and water use. Our findings indicated that the largest and lowest energy consumers were the manufacturing and construction sectors, while agriculture accounted for the largest share in water use. During the three time intervals, the cumulative effects increased the EW use, but the contributions were declining. Further, these effects had a more prominent influence on water use than energy consumption; GDP value-added effect, income improvement effect, and population-scale effect increased the EW use, while intensity effect played a vital role in decreasing EW use during the study period. Notably, the industrial structure effect had a seesaw role during 2000–2006, which led to a tradeoff between various driving factors. In future sustainable issues, policymakers should pay more attention to energy-saving than water-saving to achieve the national energy and water conservation targets.

Imaging abnormal copper/iron with effective fluorescent tools is essential to comprehensively put insight into many pathological events. However, conventional coordination‐based detection is mired in the fluorescence quenching induced by paramagnetic Cu(II)/Fe(III). Moreover, the strong chelating property of the probe will consume dissociative metal ions and inevitably interfere with the physiological microenvironment. Here, a new strategy is developed by employing this aberrant Cu(II)/Fe(III) to catalyze bond cleavage for fluorescent imaging of them. A short series of near‐infrared fluorescent molecules (NIRB1−NIRB6) is devised as substrates, wherein the specific C═C bonds can be effectively cleaved to activate red fluorophore by Cu(II)/Fe(III) catalyzing. Representatively, NIRB1 is applied for fluorescent imaging of Cu(II)/Fe(III) in living cells, zebrafish, and Alzheimer's disease (AD)‐afflicted mouse brains which is of significance to monitor metal safety. The successful cleavage of C═C bonds catalyzed by Cu(II)/Fe(III) enriches the application of abiotic bond cleavage reactions in metal detection, and may also inspire the development of fluorescent tools for the future diagnosis and therapy of diseases. Cu(II)/Fe(III)‐catalyzed oxidative cleavage of C═C bonds is successfully achieved, resulting in activating red fluorophore. Representatively, the amphiphilic molecule can effectively cleave the specific C═C bonds in living cells and zebrafish, especially in AD‐afflicted mouse brains, wherein turn‐on fluorescence is desirable for in vivo imaging‐guided explorations in the presence of paramagnetic metals.

Deep NIR organic phototheranostic molecules generally have large π‐conjugation structures and show highly hydrophobic properties, thus, forming strong π–π stacking in the aqueous medium, which will affect the phototheranostic performance. Herein, an end‐group strategy is developed to lift the performance of NIR‐II emitting photosensitizers. Extensive characterizations reveal that the hydrogen‐bonding interactions of the hydroxyl end group can induce a more intense π–π electronic coupling than the chlorination‐mediated intermolecular forces. The results disclose that π–π stacking will lower fluorescence quantum yield but significantly benefit the photodynamic therapy (PDT) efficiency. Accordingly, an asymmetrically substituted derivative (BTIC‐δOH‐2Cl) is developed, which shows balanced phototheranostic properties with excellent PDT efficiency (14.6 folds of ICG) and high NIR‐II fluorescence yield (2.27%). It proves the validity of the end‐group strategy on controlling the π–π interactions and rational tuning the performance of NIR‐II organic phototheranostic agents. The hydrogen‐bonding interactions of the hydroxy end group can induce a more intensive π–π electron coupling than the chlorination‐mediated intermolecular forces. π–π stacking will lower fluorescence quantum yield but significantly benefit the PDT efficiency. Therefore, by this end‐group strategy, the phototheranostic properties of the photosensitizers are finely tuned, and a more effective NIR‐II fluorescence‐guided PDT is accomplished.

Foreign objects such as kites, nests and balloons, etc., suspended on transmission lines may shorten the insulation distance and cause short-circuits between phases. A detection method for foreign objects on transmission lines is proposed, which combines multi-network feature fusion and random forest. Firstly, the foreign object image dataset of balloons, kites, nests and plastic was established. Then, the Otus binarization threshold segmentation and morphology processing were applied to extract the target region of the foreign object. The features of the target region were extracted by five types of convolutional neural networks (CNN): GoogLeNet, DenseNet-201, EfficientNet-B0, ResNet-101, AlexNet and then fused by concatenation fusion strategy. Furthermore, the fused features in different schemes were used to train and test random forest, meanwhile, the gradient-weighted class activation mapping (Grad-CAM) was used to visualize the decision region of each network, which can verify the effectiveness of the optimal feature fusion scheme. Simulation results indicate that the detection accuracy of the proposed method can reach 95.88%, whose performance is better than the model of a single network. This study provides references for detection of foreign objects suspended on transmission lines.

Meat plays a significant role in human diets, providing a rich source of high-quality protein. With advancements in technology, research in the field of meat preservation has been undergoing dynamic evolution. To gain insights into the development of this discipline, the study conducted an analysis and knowledge structure mapping of 1672 papers related to meat preservation research within the Web of Science Core Collection (WOSCC) spanning from 2001 to 2023. And using software tools such as VOSviewer 1.6.18 and CiteSpace 5.8.R3c allowed for the convenient analysis of the literature by strictly following the software operation manuals. Moreover, the knowledge structure of research in the field of meat preservation was synthesized within the framework of “basic research—technological application—integration of technology with fundamental research,” aligning with the research content. Co-cited literature analysis indicated that meat preservation research could be further categorized into seven collections, as well as highlighting the prominent role of the antibacterial and antioxidant properties of plant essential oils in ongoing research. Subsequently, the future research direction and focus of the meat preservation field were predicted and prospected. The findings of this study could offer valuable assistance to researchers in swiftly comprehending the discipline’s development and identifying prominent research areas, thus providing valuable guidance for shaping research topics.