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Neutrophils act as a “double-edged sword” in the tumor microenvironment by either supporting or suppressing tumor progression. Thus, eliciting a neutrophil antitumor response remains challenging. Here, we showed that tumor cell–derived microparticles induced by methotrexate (MTX-MP) acts as an immunotherapeutic agent to activate neutrophils, increasing the tumor-killing effect of the cells and augmenting T-cell antitumor responses. We found that lactate induced tumor-associated neutrophils to elevate expression of programmed cell death protein 1 (PD-1) and that PD-1+ neutrophils had the properties of N2 neutrophils and suppressed T-cell activation through PD-1/programmed death-ligand 1 (PD-L1) signaling. By performing ex vivo experiments, we found that MTX-MPs–activated neutrophils had reduced surface expression of PD-1 as a result of PD-1 internalization and degradation in the lysosomes, leading to the cells showing a decreased capacity to suppress T-cell responses. In addition, we also found that MTX-MP–activated neutrophils released neutrophil elastase which could kill tumor cells and disrupt tumor stroma, leading to increased T-cell infiltration. Furthermore, using a combination of anti–PD-L1 and MTX-MPs, we observed that long-term survival increased in a mouse model of lung cancer. Collectively, these findings highlight the potential use of a combination of anti–PD-L1 and MTX-MPs to enhance the therapeutic effect of anti–PD-L1 alone.

A facile strategy for the tunable preparation of difunctionalized alicyclic amines and 2-alkylquinoxalines through oxoammonium salt-promoted cascade reactions of saturated cyclic amines with 1,3/1,4-dinucleophiles is presented.

Arid, semi-arid, and semi-humid regions (drylands) with fragile ecological balance have undergone dramatic climate change in past decades, and how the desertification will change under a continuous warming background still remain uncertain. In this study, the bias-corrected Community Earth System Model outputs from Coupled Model Intercomparison Project phase 5 were dynamically downscaled using the Weather Research and Forecasting (WRF) model, based on which the evolution trend of desertification over northern China (NC) in the past (1972–2000) and the near future period (2021–2050) under the RCP8.5 scenario were analyzed using the dune mobility index, and the impacts of climate change on the intensification or reversal of desertification over NC in the near future were explored. The results show that WRF downscaling can reproduce the desertification changes over NC in the past. The regions with a high risk of desertification are mainly located on the border of the desert and gobi. Under a rapidly warming climate in the near future, desertification will likely reverse in most regions of NC, especially for regions north of 40°N over NC. Potential evapotranspiration changes will exacerbate desertification, while precipitation changes will promote rehabilitation, and wind speed changes show obvious local impacts on desertification. The results in this study imply that, with rising temperatures in the future, the extent of desertification will not always continue, desertification will likely reverse at the front and margin of deserts and gobi, and responses of desertification to climate change have significant spatial differences.

Foams made of immiscible polymer blends have attracted great interest in both academia and industry, because of the integration of desirable properties of different polymers in a hybrid foam. However, the foamability and end-use properties are hampered because of the poor interfacial strength within the immiscible blends. Furthermore, few investigations have been carried out on the mechanisms by which interfacial strength and structure affect the foamability of polymer blends. In this work, two different reactive interfacial compatibilizers, i.e., poly(styrene

As a two-dimensional electromagnetic metamaterial, the cross-polarization conversion (CPC) metasurface is thin, easy to develop, and has attracted wide attention. However, existing CPC cell surface designs still rely on inefficient full-wave numerical simulation. Although some researchers have explored deep learning CPC metasurface structure design methods, the generated metasurface patterns are of poor quality. In this paper, an on-demand design method for cross-polarization conversion metasurface based on depth-generation model is proposed. Firstly, Wasserstein generative adversarial network (WGAN) is used to reverse design CPC metasurface, and Wasserstein distance is introduced to replace JS divergence and KL divergence to optimize the target. The problem of training difficulty caused by gradient elimination of original generative adversarial network (GAN) is fundamentally solved. Secondly, in the WGAN model, U-Net architecture generator is used to generate images, which greatly improves the surface image quality of CPC. In addition, a simulator composed of convolutional neural network (CNN) is also added in this paper to carry out forward prediction of S-parameter spectrum diagram. By inputting the patterns generated by WGAN into the simulator, the corresponding S-parameter spectrum diagram is generated and compared with the real S-parameter spectrum diagram, so as to verify whether the surface patterns of generated elements meet the requirements. The depth generation model proposed in this paper organically combines the forward spectrum prediction model and the reverse CPC metasurface structure design model, so that the CPC metasurface structure satisfying the expected electromagnetic response can be designed quickly on demand. This on-demand design method is expected to promote the rapid design, fabrication and application of electromagnetic devices.

supplementary figures 1-7 and table S1

Neutrophils act as a “double-edged sword” in the tumor microenvironment by either supporting or suppressing tumor progression. Thus, eliciting a neutrophil antitumor response remains challenging. Here, we showed that tumor cell–derived microparticles induced by methotrexate (MTX-MP) acts as an immunotherapeutic agent to activate neutrophils, increasing the tumor-killing effect of the cells and augmenting T-cell antitumor responses. We found that lactate induced tumor-associated neutrophils to elevate expression of programmed cell death protein 1 (PD-1) and that PD-1+ neutrophils had the properties of N2 neutrophils and suppressed T-cell activation through PD-1/programmed death-ligand 1 (PD-L1) signaling. By performing ex vivo experiments, we found that MTX-MPs–activated neutrophils had reduced surface expression of PD-1 as a result of PD-1 internalization and degradation in the lysosomes, leading to the cells showing a decreased capacity to suppress T-cell responses. In addition, we also found that MTX-MP–activated neutrophils released neutrophil elastase which could kill tumor cells and disrupt tumor stroma, leading to increased T-cell infiltration. Furthermore, using a combination of anti–PD-L1 and MTX-MPs, we observed that long-term survival increased in a mouse model of lung cancer. Collectively, these findings highlight the potential use of a combination of anti–PD-L1 and MTX-MPs to enhance the therapeutic effect of anti–PD-L1 alone.

Supplementary Data from Development of Novel Aptamer-Based Targeted Chemotherapy for Bladder Cancer

Bladder cancer is common worldwide, with most patients presenting with nonmuscle invasive disease. Multiple intravesical recurrences lead to reduced quality of life and high costs for patients with this form of bladder cancer. Intravesical chemotherapy aimed at reducing recurrence is the standard-of-care but has significant side effects from nonspecific cytotoxicity to normal urothelium. Importantly, toxicity limits doses that can be administered. Thus, tumor-specific drug targeting could reduce toxicity and enhance effectiveness by allowing higher doses. Here, using cell internalization systematic evolution of ligands by exponential enrichment (SELEX), we identify a novel bladder cancer-specific, chemically modified nucleic acid aptamer that can be preferentially internalized into tumor cells but not normal urothelial cells. The 35-nucleotide B1 aptamer is internalized into bladder cancer cells through clathrin-mediated endocytosis and macropinocytosis. As proof of principle, a B1-guided DNA nanotrain delivery vehicle for epirubicin was constructed as a targeted intravesical chemotherapy. The B1-nanotrain-epirubicin construct exhibited selective cytotoxicity towards bladder cancer cells and outperformed epirubicin in murine orthotopic xenograft models of human bladder cancer. This aptamer-based delivery system makes targeted chemotherapy possible for bladder cancer, providing a compelling rationale for clinical development.Significance:These findings identify a bladder cancer–specific aptamer that can be used for targeted delivery of chemotherapy, potentially reducing toxicity and enhancing therapeutic efficacy.

The external bacteria will inevitably invade the wound, attach, and subsequently colonize on the wound surface during surgery and biomedical operations, which slows down the process of wound healing and tissue repair, remaining a significant threat to human health. Therefore, developing a smart antibacterial surface has become the focus of antimicrobial research field, which has important social and economic significance. Herein, we present a simple route towards producing ionic interaction-driven switchable multifunctional antibacterial surfaces that decrease bacteria attachment and inactivate attached microorganisms. Briefly, the graded surface was constructed by surface-initiated atom transfer radical polymerization on silicon substrate consisting of antifouling component poly (3-sulfopropyl methacrylate potassium salt) (PSPMA) brushes, an antibacterial positive-charged components lysozyme (LYZ) and hexadecyl trimethyl ammonium bromide (CTAB) were loaded on negative-charged sulfonate groups via electrostatic interaction. The resultant brushes grafted surfaces exhibited more than ~95.5% bactericidal efficacy, and ~92.8% releasing rate after introducing contra-ions (Na+ & Cl-) against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. More importantly, the ionic interaction-driven method used in this work is straightforward to produce renewable antibacterial surfaces. To further extend the applications, we construct smart cotton fabric to develop Fabric-PSPMA/LYZ and Fabric-PSPMA/Chitosan brushes which can promote wound healing and tissue repair. This work will assist in the wider utilization of the switchable antibacterial functionalization of biomedical materials.

Bilayer hydrogels are attracting tremendous attention for their capability to integrate several different functions on the two sides of the gel, that is, imparting the gel with Janus characteristics, which is highly desired in many engineering and biomedical applications including soft actuators, hydrogel patches, and wearable electronics. However, the preparation process of the bilayer materials usually involves several complicated steps and is time-consuming, while the interfacial bonding is another main concern. Here, a simple and versatile method is proposed to obtain bilayer hydrogels within just one step based on the method of introducing viscosity contrast of the precursors for different layers. The bilayer structure can be well maintained during the whole preparation process with a constrained interfacial molecular exchange to ensure the strong bonding strength. The key requirements for forming distinct bilayer structures in situ are studied and discussed in detail. Bilayer hydrogels with different chemical designs are prepared via this strategy to tailor the good distribution of desired functions for soft actuators, wound healing patches, and wearable electronics. We believe that the strategy illustrated here will provide new insights into the preparation and application of bilayer materials.

As sustainable development has been widely recognized as an essential topic in the continuous advancement of human history, a wide variety of organizations around the world, including companies, have integrated sustainability into their development paths. A typical example of the integration of sustainability with a company's growth path is the company's sustainability report (SR). However, notwithstanding more and more companies are joining the sustainability reporting cohort, the standards for reporting are not uniform and the quality of reporting is uneven, which ultimately affects the quality of the organizational sustainability and the sustainability of the world as a whole. The purpose of this study is to investigate the nature and extent of sustainability reporting practices of a brewing company located in Minsk, Belarus. Data were collected from the company’s latest 2019 SR. Deductive content analysis was used to analyse the data, and the coding scheme used for content analysis was developed based on indicators from the Global Reporting Initiative (GRI). The results indicate a lack of disclosure of the SR of Belarusian brewing companies in terms of the content of biodiversity conservation and environmental complaint mechanisms. The results provide several practical implications for Belarusian brewing companies, regulators, and policymakers This study is one of the first to investigate the nature and extent of sustainability reporting practices in Belarusian brewing companies.

This article examines the impact of China’s Belt and Road Initiative (BRI) on the Eurasian Economic Union (EAEU), with a focus on trade and investment. Using data on foreign direct investment (FDI) and trade flows between China and the EAEU member states from 2012 to 2021, the study finds a fluctuating and overall downward trend in FDI, but an overall upward trend in trade volume. The findings suggest that while there are significant opportunities for cooperation between China and the EAEU, careful management is required to minimize risks and maximize benefits for all parties involved. The study underscores the importance of collaboration in advancing regional economic integration and sustainable development of EAEU region.

For the problem that rolling bearing fault characteristics are difficult to extract accurately and the fault diagnosis accuracy is not high, an unsupervised characteristic selection method of refined composite multiscale fluctuation-based dispersion entropy (RCMFDE) combined with self-paced learning and low-redundant regularization (SPLR) is proposed, for which the fault diagnosis is carried out by support vector machine (SVM) optimized by the marine predator algorithm (MPA). First, we extract the entropy characteristics of the bearings under different fault states by RCMFDE and the introduction of the fine composite multiscale coarse-grained method and fluctuation strategy improves the stability and estimation accuracy of the bearing characteristics; then, a novel dimensionality-reduction method, SPLR, is used to select better entropy characteristics, and the local flow structure of the fault characteristics is preserved and the redundancy is constrained by two regularization terms; finally, using the MPA-optimized SVM classifier by combining Levy motion and Eddy motion strategies, the preferred RCMFDE is fed into the MPA–SVM model for fault diagnosis, for which the obtained bearing fault diagnosis accuracy is 97.67%. The results show that the RCMFDE can effectively improve the stability and accuracy of the bearing characteristics, the SPLR-based low-dimensional characteristics can suppress the redundancy characteristics and improve the effectiveness of the characteristics, and the MPA-based adaptive SVM model solves the parameter randomness problem and, therefore, the proposed method has outstanding superiority.

A film with elaborate microstructures that offers biomimetic properties and multi functionalities is highly desired in wound healing. Here, we develop an aligned hydrogel fiber film integrated with multi-active constituents to promote wound healing. Such fiber films are designed and constructed by photo-crosslinking the methacrylate gelatin (GelMA) doped with silver nanoparticles (Ag NPs) and iridium nanoparticles coated with polyvinylpyrrolidone (PVP-Ir NPs) in the precursor solution using electrospinning. The nature of GelMA hydrogel and the aligned arrangement of nanofibers endow the film with high-water content, self-degradability, improved bionic characteristics, oriented cell growth, and improved cell proliferation and migration. Moreover, the encapsulated nanozymes and Ag NPs offer the fiber film with superior reactive oxygen species (ROS) scavenging and antibacterial capability. The infected wound model shows that the multi-active hydrogel fiber film can reduce inflammation by killing bacteria and decomposing ROS, which accelerates the growth of new blood vessels and granulation tissue. Benefitting from these features, the versatile aligned GelMA fiber film demonstrates the clinically translational potential for wound healing.

Background: Mesenchymal stem cells (MSCs) are considered a promising tool for treating cerebral ischemic injury. However, their poor survival after transplantation limits their therapeutic effect and applications. Salidroside has been reported to exert potent cytoprotective and neuroprotective effects. This study aimed to investigate whether salidroside could improve MSC survival under hypoxic-ischemic conditions and, subsequently, alleviate cerebral ischemic injury in a rat model.Methods: MSCs were pretreated by salidroside under hypoxic-ischemic conditions. The cell proliferation, migratory capacity, and apoptosis were evaluated by means of Cell Counting Kit (CCK)-8, transwell assay, and flow cytometry. MSCs pretreated with salidroside were transplanted into the rats subsequent to middle cerebral artery occlusion. The grip strength, 2,3,5-triphenyltetrazolium chloride, and hematoxylin-eosin staining were used to analyze the therapeutic efficiency and pathological changes. The mature neuron marker NeuN and astrocyte marker GFAP in the focal area were detected by immunofluorescence.Results: These results indicated that salidroside promoted the proliferation, migration and reduced apoptosis of MSCs under hypoxic-ischemic conditions. In vivo experiments revealed that transplantation of salidroside-pretreated MSCs strengthened the therapeutic efficiency by enhancing neurogenesis and inhibiting neuroinflammation in the hippocampal CA1 area after ischemia.Conclusion: Our results suggest that pretreatment with salidroside could be an effective strategy to enhance the cell survival rate and the therapeutic effect of MSCs in treating cerebral ischemic injury.

Multi-stage variable inclination equal-thickness screen (MSVIETS) is widely used in separating coal and mineral particles because of its large production capacity and good screening performance. In...

Water-heat transport in frozen soil impacts the hydrological processes in cold region through its influences on the surface energy budget and water storage. In this study, sensitivities of soil water-heat transport simulations to parameterizations of soil permeability, supercooled water and freezing temperature threshold that determines phase change criteria were assessed in the Noah with multi-parameterization (Noah‐MP) land surface model. The results showed that Noah-MP well reproduce the seasonal variations in soil temperature and moisture in the freeze-thaw (FT) process, while it still involves biases in soil temperature and moisture simulations with RMSE of 4.35 ℃ and 0.068 mm /mm at shallow layer during soil thawing period. Performances of Noah-MP in soil water-heat transport simulations are not very sensitive to the optional combinations of soil permeability and supercooled water parametrizations. Nevertheless, instead of constant freezing temperature, a virtual temperature implemented to redefine the phase change criteria improves soil moisture simulations in the FT process evidently by about 20%–50% bias reduction, especially during soil thawing period, and the simulated soil water–heat coupling relation is consistent with the observations. Global simulations further validate the improvements of implemented frozen soil parameterizations in Noah-MP. Results in this study emphasize the importance of phase change criteria choice in land surface model for frozen soil hydrothermal regime simulations.

Herein we describe a convenient method for multiple C(spsup3/sup)-H bond functionalization of saturated cyclic amines through oxoammonium salt-promoted oxidation to afford a β-oxo cyclic iminium ion as a key intermediate, followed by cascade addition with thiocyanate and diverse N-, O-, and S-containing nucleophiles in the green solvent and EtOH. Notably, chiral spiro azapolyheterocycles were prepared enantioselectively (gt;20:1 dr, up to 99% ee) when cysteine or serine esters were used as substrates. Moreover, the concise late-stage modification of several natural product derivatives was accomplished using this method.

Background This study aimed to develop and validate a lasso regression algorithm model which was established by correlation factors of bone mineral density (BMD) and could be accurately predicted a high-risk population of primary osteoporosis (POP). It provides a rapid, economical and acceptable early screening method for osteoporosis in grass-roots hospitals. Methods We collected 120 subjects from primary osteoporosis screening population in Zhejiang Quhua Hospital between May 2021 and November 2021 who were divided into three groups (normal, osteopenia and osteoporosis) according to the BMD T-score. The levels of three micro-RNAs in the plasma of these people were detected and assessed by qRT-PCR. At the same time, the levels of β-CTX and t-P1NP in serum of the three groups were determined. Based on the cluster random sampling method, 84 subjects (84/120, 70%) were selected as the training set and the rest were the test set. Lasso regression was used to screen characteristic variables and establish an algorithm model to evaluate the population at high risk of POP which was evaluated and tested in an independent test cohort. The feature variable screening process was used 10-fold cross validation to find the optimal lambda. Results The osteoporosis risk score was established in the training set: Risk of primary osteoporosis score (RPOPs) = -0.1497785 + 2.52Age − 0.19miR21 + 0.35miR182 + 0.17β-CTx. The sensitivity, precision and accuracy of RPOPs in an independent test cohort were 79.17%, 82.61% and 75%, respectively. The AUC in the test set was 0.80. Some risk factors have a significant impact on the abnormal bone mass of the subjects. These risk factors were female (p = 0.00013), older than 55 (p p = 0.0091) who should pay more attention to their bone health. Conclusion In this study, we successfully constructed and validated an early screening model of osteoporosis that is able to recognize people at high risk for developing osteoporosis and remind them to take preventive measures. But it is necessary to conduct further external and prospective validation research in large sample size for RPOPs prediction models.

Development of polymer-based flooding technology to improve oil recovery efficiency, water dispersion copolymerization of acrylamide, cationic monomer methacryloxyethyltrimethyl ammonium chloride (METAC), and anionic monomer acrylic acid (AA) were carried out in aqueous ammonium sulfate solution with polyvinyl pyrrolidone (PVP) as the stabilizer. The copolymers were characterized by

Adversarial examples (AEs) make Internet-of-Things (IoT) systems to face a great challenge. The tiny fluctuations in AEs mislead the learning model, let the model accept, and make wrong decisions. So, accurately identifying AEs is significant for improving the robustness in IoT systems. In this article, a method to identify AEs for time-series data is proposed. We analyze the characteristics of adversarial time-series examples and normal time-series samples and propose a time-series representation method. The tiny fluctuations in AEs are easily discovered by this representation. A metric is also designed to support this representation method to identify AEs with supervised learning and unsupervised learning methods. Our representation method and the metric is applied with supervised learning and unsupervised learning methods to identify time series in real data set and data sets in the official UCR repository. The experimental results show that our method has a great ability to identify AEs, compared to previous approaches.

Hydrophobic micro-porous membrane such as polyvinylidene fluoride (PVDF) with excellent thermal-/chemical-stability and low surface energy has received extensive attention in industrial water treatment and sustainable energy conversion. However, undesirable contaminants caused by inevitable proteins or microorganisms adhesion may lead to a rapid loss of separation efficiency, which significantly deteriorate their porous structures and eventually limit their practical performance. Herein, we present a scalable approach for fabricating comb-like copolymer modified PVDF membranes (PVDF-PN@AgNPs) that prevent bacteria from proliferating on the surface and temperature-controlled release of adhered contaminants. Comb-like structured copolymers were imparted to a polydopamine (PDA)-treated PVDF membrane by Michael addition reaction, which enabled a covalent binding of comb-like structured copolymers to the membrane. Such unique structural design of grafted copolymer, containing hydrophilic side chain and temperature-responsive chain backbone, stably prevents bacteria adhesion and provides reversible surface wettability. Therefore, the resultant membranes were evaluated to prevent bacterial adhesion, high touch-killing efficiency and temperature-controlled contaminants release (~99% of protein and ~75% of bacteria). Moreover, with the collapse and stretch of grafted copolymer chain backbone, the synthetic membrane further reversibly adjusted inner micro-porous structure and surface wettability, which eventually helped to achieve variable water fluid transport efficiency. This study not only provides a feasible structural design for stably coping with the challenging of antifouling and subsequent contamination adhesion of PVDF membrane, but also potentially answers the significant gap between lab research advances and practical application, particularly in the industrial membrane field.

Development of smart switchable surfaces to solve the inevitable bacteria attachment and colonization has attracted much attention; however, it proves very challenging to achieve on-demand regeneration for noncontaminated surfaces. We herein report a smart, host-guest interaction-mediated photo/temperature dual-controlled antibacterial surface, topologically combining stimuli-responsive polymers with nanobactericide. From the point of view of long-chain polymer design, the peculiar hydration layer generated by hydrophilic poly(2-hydroxyethyl methacrylate) (polyHEMA) segments severs the route of initial bacterial attachment and subsequent proliferation, while the synergistic effect on chain conformation transformation poly(N-isopropylacrylamide) (polyNIPAM) and guest complex dissociation azobenzene/cyclodextrin (Azo/CD) complex greatly promotes the on-demand bacterial release in response to the switch of temperature and UV light. Therefore, the resulting surface exhibits triple successive antimicrobial functions simultaneously: (i) resists ∼84.9% of initial bacterial attachment, (ii) kills ∼93.2% of inevitable bacteria attack, and (iii) releases over 94.9% of killed bacteria even after three cycles. The detailed results not only present a potential and promising strategy to develop renewable antibacterial surfaces with successive antimicrobial functions but also contribute a new antimicrobial platform to biomedical or surgical applications.

Numerous efforts to fabricate antimicrobial surfaces by simple yet universal protocols with high efficiency have attracted considerable interest but proved to be particularly challenging. Herein, we designed and fabricated a series of antimicrobial polymeric coatings with different functions from single to multiple mechanisms by selectively utilizing diethylene glycol diglycidyl ether (PEGDGE), polylysine, and poly[glycidylmethacrylate-co-3-(dimethyl(4-vinylbenzyl)ammonium)propyl sulfonate] (poly(GMA-co-DVBAPS)) via straightforward mussel-inspired codeposition techniques. Bactericidal polylysine endowed the modified surfaces with a high ability (∼90%) to kill attached bacteria, while PEGDGE components with unique surface hydration prevented bacterial adhesion, avoiding the initial biofilm formation. Moreover, excellent salt-responsive poly(GMA-co-DVBAPS) enabled reactant polymeric coatings to change chain conformations from shrinkable to stretchable state and subsequently release >90% attached bacteria when treated with NaCl solution, even after repeated cycles. Therefore, the obtained polymeric coatings, polydopamine/poly(GMA-co-DVBAPS) (PDA/PDV), polydopamine/polylysine/poly(GMA-co-DVBAPS) (PDA/l-PDV), and polydopamine/polylysine/poly(GMA-co-DVBAPS)/diethylene glycol diglycidyl ether (PDA/l-PDV-PEGDGE), controllably realized functions from single and dual to multiple antimicrobial mechanisms, as evidenced by long-term antifouling activity to bacteria, high bactericidal efficiency, and salt-responsive bacterial regeneration performance with several bacterial killing-release cycles. This study not only contributes to mussel-inspired chemistry for polymeric coatings with controllable functions but also provides a series of reliable and highly efficient antimicrobial surfaces for potential biomedical applications.

Selective cleavage and functionalization of C–N/C–C bonds in saturated cyclic amines under the promotion of oxoammonium salt and tert-butyl hydroperoxide in the presence of different additives have been developed. To be specific, cascade cleavage and reconstruction of C–N and C–C bonds took place under acidic conditions to provide pyrrolidin-2-ones. Under basic conditions, on the other hand, selective cleavage and functionalization of C–C bonds occurred to afford multi-functionalized acyclic N-formal amines. In addition, studies for revealing the intriguing reaction mechanisms have also been performed.

The high conductivity and excellent mechanical properties of polymer composites favor their application as piezoresistive strain sensors. However, developing polymer composites with desirable piezoresistance, mechanical and durable properties is challenging. Herein, we developed conductive cellulose/MWCNTs aerogels using the freeze-drying technique. Furthermore, we explored the application of the highly-sensitive piezoresistive polymer composites following supercritical carbon dioxide (ScCO2) foaming, in cellulose/MWCNTs aerogel-thermoplastic polyurethane (TPU) nanocomposites. Conductive polymer composite (CPC) foams exhibited a significantly low percolation threshold (MWCNTs loading of ∼0.07 vol%) and high piezoresistive sensitivity (GF value of 7.84) owing to the low density (∼0.15 g cm−3) of cellulose/MWCNTs, high porosity (90%) and high electric conductivity (2.04 S m−1). The microcellular structure of composite foams was stable with regard to energy loss coefficient and piezoresistance after several compression cycles (1000 cycles). The behavior of the prepared CPC foams under different conditions was evaluated. The findings of the study showed that the piezoresistive sensors can be used in real-time monitoring of human movement.

In recent decades, increasing efforts have been made for the development of more efficient and sustainable methods for the functionalization of saturated cyclic amines. This is mainly due to the following two facts: (1) simple cyclic amines are readily available with low cost; and (2) functionalized cyclic amines are synthetically and biologically highly valuable in that they are found in numerous natural products, pharmaceuticals and fine chemicals. In this review, the most recent advances in the C–H, C–N and C–C bond functionalization of saturated cyclic amines are summarized.

DNA nanotechnology is powerful in constructing programmable nanostructures with distinct dimensions, sizes, and shapes. However, natural DNA molecules are prone to nuclease degradation, thus limiting the in vivo applications of such DNA nanostructures. 2'-Fluoroarabinonucleic acid (FANA) is a chemically modified oligonucleotide with similar base pairing properties to DNA and exhibits superior physical and chemical stabilities. In this work, FANA molecules were used to construct double crossover nanostructures, and it was demonstrated that incorporation of FANA conferred nucleic acid nanostructures with increased thermal stability and stronger nuclease resistance. More importantly, FANA nanostructures were able to maintain the structural integrity in the strongly acidic environment (pH 1.2). Last, such FANA nanostructures functioned well in acting as stable carriers of small-molecule cargoes for cellular delivery in simulated gastric fluid, while the DNA counterparts were mostly degraded. Collectively, these results demonstrated that FANA self-assembly was not only a substantial complement to the structural DNA nanotechnology but also an appealing molecular tool for in vivo biomedical applications.

An efficient synthesis of β-methylsulfonylated N-heterocycles via FeCl3-catalyzed C(sp3)–H dehydrogenation and C(sp2)–H methylsulfonylation of inactivated cyclic amines with the promotion and parti...

Recently, the antisoiling performances of superhydrophobic (SH) surfaces have received much attention due to their potential applications in self-cleaning photovoltaic glass and other surfaces without the need to be rinsed with water. In this work, we systematically compared the antisoiling performances of lotus leaf and other plant leaves by first drying them in the shade and then placing them outdoors in a slight breeze for 1-2 months. The results show that after being dried in the shade, the lotus leaf and the canna leaf retain their SH properties, comparable with their fresh states. The firmiana leaf is still hydrophilic. However, when the leaves are exposed to rain, no rain drops adhere to the surface of the lotus leaf but many droplets adhere to the canna leaf. Furthermore, after being incubated outdoors in the absence of rain for 1 month, the lotus leaf retained its SH properties, the canna leaf was no longer SH, and the firmiana leaf became more hydrophilic. SEM imaging with EDS and elemental mapping all confirmed that after outdoor exposure for 1-2 months, only a small amount of dust was found on the lotus leaf but a significant amount of dust was present on the canna leaf, with even more on the firmiana leaf. These results confirm that the lotus leaf has excellent antisoiling performance. The low interactions between the lotus leaf surface and the dust particles are most likely responsible for this unique property. On the contrary, the canna leaf, and especially the firmiana leaf, do not possess this property because neither their surface microstructures nor their surface free energies are favorable to reduce interactions between the leaf surface and dust particles. This study will be helpful in designing and preparing a surface with antisoiling performance.