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Models based on MLP-Mixer architecture are becoming popular, but they still suffer from adversarial examples. Although it has been shown that MLP-Mixer is more robust to adversarial attacks compared to convolutional neural networks (CNNs), there has been no research on adversarial attacks tailored to its architecture. In this paper, we fill this gap. We propose a dedicated attack framework called Maxwell's demon Attack (MA). Specifically, we break the channel-mixing and token-mixing mechanisms of the MLP-Mixer by perturbing inputs of each Mixer layer to achieve high transferability. We demonstrate that disrupting the MLP-Mixer's capture of the main information of images by masking its inputs can generate adversarial examples with cross-architectural transferability. Extensive evaluations show the effectiveness and superior performance of MA. Perturbations generated based on masked inputs obtain a higher success rate of black-box attacks than existing transfer attacks. Moreover, our approach can be easily combined with existing methods to improve the transferability both within MLP-Mixer based models and to models with different architectures. We achieve up to 55.9% attack performance improvement. Our work exploits the true generalization potential of the MLP-Mixer adversarial space and helps make it more robust for future deployments. [ABSTRACT FROM AUTHOR]

In this study, a meta‐analysis was conducted to comprehensively analyse the effectiveness of using proximal femoral nail anti‐rotation (PFNA) and dynamic hip screws (DHS) to treat intertrochanteric fractures on postoperative surgical site infections (SSI). PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched from their inception until December 2022 to identify studies that compared PFNA and DHS in the treatment of intertrochanteric fractures. Two investigators independently screened the retrieved studies to assess their quality and verify their eligibility for inclusion. Meta‐analyses were performed with RevMan 5.4 software. Thirty studies, including 3158 patients, met the inclusion criteria. These studies included 1574 patients treated with PFNA, and 1584 were treated with DHS. The findings of the meta‐analysis revealed a significant reduction in the incidence of SSI in patients treated with PFNA compared with those treated with DHS (2.64% vs 6.76%, odds ratio [OR]: 0.40, 95% confidence intervals [CIs]: 0.28–0.57, P <.001), superficial SSI (2.58% vs 5.01%, OR: 0.53, 95% CIs: 0.33–0.85, P =.008) and deep SSI (1.26% vs 3.43%, OR: 0.41, 95% CIs: 0.19–0.92, P =.03). PFNA was more effective than DHS in reducing the incidence of SSI. Even so, significant variations in sample sizes among the included studies meant that the methodology for some studies had qualitative deficiencies. Therefore, additional studies with large sample sizes are needed to validate these results. [ABSTRACT FROM AUTHOR]

One of the crucial issues for applying electret/triboelectric power generators in the Internet of Things (IoT) is to take full advantage of specific high voltage signals and enable self-powered sensing. Therefore, inspired by Miura-origami, we present an innovative origami power generator (OPG) constructed from only one piece of electret thin film. The Miura-origami architecture realizes a generator with excellent deformability and stretchability and makes it unnecessary for any auxiliary support structure during the compress-release cycle. Various parameters of the generator are intensively investigated, including the excitation accelerations, excitation displacements, numbers of power generation units and deformation degree of the device. When stimulated with 5.0 g acceleration at 15 Hz frequency, the generator with 8 generation units can obtain an instantaneous peak-to-peak voltage and a remarkable optimum peak power of 328 V and 2152 μW at 50 MΩ, respectively. In addition, the regulable shape and multiple generation modes of the device greatly improve its applicability in various vibration energy collection requirements. Based on the above results, a hexagonal electret generator integrated with six-phase OPGs is developed as a "Buoy on Sky," after which the signal waveforms generated from internal power generators are recognized with 92% accuracy through a neural network algorithm that identifies the vibration conditions of transmission lines. This work demonstrates that a fusion of origami art and energy conversion techniques can achieve a multifunctional generator design satisfying the requirements for IoT applications. [ABSTRACT FROM AUTHOR]

Inspired by an electromagnetic generator containing multi-pole radial ring magnets, we designed a bipolar electret rotatory power generator (e-RPG) with a multi-phase core-shell structure to boost output performance and achieve high-precision self-sensing capabilities. A selectively localized rotary corona discharging method is invented to uniformly inject both positive and negative charges into a single electret’s curved surface. The experimental results show that the output power of the bipolar-charged e-RPG is increased to 384% compared with those of positive or negative charging alone, which is consistent with the results obtained from the theoretical model. By introducing the core-shell-structured multi-phase electrode design, both the rotation direction and speed can be precisely detected. The frequency sensitivity and linearity $\text{R}^{2}$ (coefficient of determination) are up to 3.0 rpm/Hz and 99.9%, respectively. The proposed e-RPG has potential applications in the Internet of Things, self-powered sensing and self-sensing of rotational motions. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinases (MMPs) are important biomarkers for a number of diseases. Thus, the precise determination of MMP activity is of crucial importance. Herein, we report a ratiometric fluorescence method for the sensitive and selective sensing of MMP activity. A number of positively charged MMP substrates (polypeptides) were designed and prepared. These polypeptides could induce aggregation of a negatively charged perylene diimide derivative (PC1). As a result, excimer fluorescence of PC1 was observed. Addition of the corresponding MMP resulted in cleavage of the polypeptide chain and dis-aggregation of PC1, which led to turning on of the PC1 monomer fluorescence. Based on the ratio of the monomer (545 nm, IM) and the excimer (680 nm, IM) fluorescence intensity changes, a ratiometric method I545/I680) was established to detect MMP activity. The enzymatic activity of a number of MMPs (MMP-1, 2, 3, 7, 9 and 13) could be determined with a limit of detection of 4.8, 2.2, 16, 6.0, 1.7 and 5.5 ng mL−1, respectively. Using MMP-2 and MMP-9 as examples, flavonoid herbal extracts as potential inhibitors were studied. It was observed that mangiferin, apigenin, quercetin and isoliquiritigenin had significant inhibiting effects on the enzyme activity. And these herbal extracts also inhibited tumor cell metastasis. Moreover, the developed strategy was also employed to determine the concentration of MMP-9 in human saliva samples. Since the method relies on only noncovalent interactions between the polypeptide and PC1, no covalent labeling of fluorescence dye on the polypeptide substrate is required, and the method is thus simple, broad-spectrum inexpensive and effective. It has the potential to be developed into a clinical test kit. [ABSTRACT FROM AUTHOR]

Background: Spinal cord injury (SCI) is an inflammatory condition, and excessive adenosine triphosphate (ATP) is released into the extracellular space, which can be catabolized into adenosine by CD73. Extracellular vesicles have been designed as nano drug carriers in many diseases. However, their impacts on delivery of CD73 after SCI are not yet known. We aimed to construct CD73 modified extracellular vesicles and explore the anti-inflammatory effects after SCI. Methods: CD73 engineered extracellular vesicles (CD73+ hucMSC-EVs) were firstly established, which were derived from human umbilical cord mesenchymal stem cells (hucMSCs) transduced by lentiviral vectors to upregulate the expression of CD73. Effects of CD73+ hucMSC-EVs on hydrolyzing ATP into adenosine were detected. The polarization of M2/M1 was verified by immunofluorescence. Furthermore, A2aR and A2bR inhibitors and A2bR knockdown cells were used to investigate the activated adenosine receptor. Biomarkers of microglia and levels of cAMP/PKA were also detected. Repetitively in vivo study, morphology staining, flow cytometry, cytokine analysis, and ELISA assay, were also applied for verifications. Results: CD73+ hucMSC-EVs reduced concentration of ATP and promoted the level of adenosine. In vitro experiments, CD73+ hucMSC-EVs increased macrophages/microglia M2:M1 polarization, activated adenosine 2b receptor (A2bR), and then promoted cAMP/PKA signaling pathway. In mice using model of thoracic spinal cord contusion injury, CD73+ hucMSC-EVs improved the functional recovery after SCI through decreasing the content of ATP in cerebrospinal fluid and improving the polarization from M1 to M2 phenotype. Thus, the cascaded pro-inflammatory cytokines were downregulated, such as TNF-α, IL-1β, and IL-6, while the anti-inflammatory cytokines were upregulated, such as IL-10 and IL-4. Conclusions: CD73+ hucMSC-EVs ameliorated inflammation after spinal cord injury by reducing extracellular ATP, promoting A2bR/cAMP/PKA pathway and M2/M1 polarization. CD73+ hucMSC-EVs might be promising nano drugs for clinical application in SCI therapy. [ABSTRACT FROM AUTHOR]

The ingredients of makeup removers are very complex, and it is difficult to distinguish the brand and authenticity of makeup removers simply by employing traditional ingredient analysis. In this work, based on the controlled self-assembly of perylene probes, a novel fluorescence sensing strategy was successfully developed to distinguish the brand and authenticity of makeup removers. Four charged perylene derivatives were synthesized and utilized as the sensing elements. It was found that the perylene probes were soluble and existed in equilibrium between their aggregated and free monomeric forms in neutral aqueous solution. The disaggregation of the probes occurred in the presence of surfactants or alcohols. Moreover, various degrees of disaggregation and the corresponding turn-on fluorescence were observed in the presence of different kinds of surfactants and alcohols. A novel four-channel sensor array based on the probes was then established, and successfully utilized for the discrimination of alcohols and surfactants. In addition, based on the fact that surfactants and alcohols are the main components of makeup removers, the sensor array was also successfully employed to discriminate makeup remover waters. Using our devised sensor array, makeup removers could be easily distinguished from the daily used liquid goods, and the nine brands of commercial makeup removers could also be easily differentiated from each other. The authenticity of makeup removers could also be identified with high accuracy. [ABSTRACT FROM AUTHOR]

A rational design of a benzoperylene probe BP-3 with positive charge allows for turn-on excimer emission, and wash-free cell membrane imaging. BP-3 possesses excellent chemical, thermal and photo stability. And the Stokes shift of the excimer emission is considerably large (90–100 nm), which very much avoids the background fluorescence interference. [ABSTRACT FROM AUTHOR]

A sensitive sandwich immunoassay for the sensing of human epididymis protein 4 (HE4) is developed based on aggregation-induced emission probe doped silica nanoparticles. Fluorescent silica nanoparticles (TSiO2) with excellent performance were prepared using a tetraphenylethylene based probe (TPE-C4-4) to produce a controlled aggregation effect, and HE4 was detected using antibody-functionalized fluorescent silica nanoparticles. The fluorescent silica nanoparticles possess good photophysical properties. The TSiO2 NPs were surface modified with carboxyl groups, and the antibody was covalently attached onto the surface of the nanoparticles. In addition, magnetic beads were modified with N-hydroxysulfosuccinimide sodium salt (NHS) on their surface, capable of forming stable peptide bonds with the antibody. TSiO2 NPs modified by an antibody and the magnetic beads modified by an antibody were used for the sandwich immunoassay for HE4 protein. The assay is quite sensitive and selective. The detection limit of HE4 is estimated to be 40 pM. The assay shows promising applications for the early diagnosis of ovarian cancer and the development of ovarian cancer-related drugs. [ABSTRACT FROM AUTHOR]

This communication reports novel luminescent rhenium(I)–polypyridine complexes appended with a perylene diimide (PDI) or benzoperylene monoimide (BPMI) moiety through a non‐conjugated linker. The photophysical and photochemical properties originating from the interactions of the metal polypyridine and perylene units were exploited to afford new cellular reagents with thiol‐sensing capability and excellent photocytotoxic activity. [ABSTRACT FROM AUTHOR]

A perylene probe PC4 is exploited as a membrane intercalating conjugated oligoelectrolyte for efficient antimicrobial photodynamic therapy. PC4 can also serve as a fluorescent microbial cell death marker. [ABSTRACT FROM AUTHOR]

A perylene probe PC4 is explored as a smart lysosome-targeted photosensitizer. It can efficiently kill cancer cells and also mark dead cells with bright fluorescence emission in nuclei for real-time monitoring and assessing of the photodynamic therapeutic efficiency. [ABSTRACT FROM AUTHOR]

We report benzo[ghi]perylene (BzP) and coronene (Cron) as multimode fluorescent probes for accurate monitoring and direct visualization of monomer–micelle transitions in surfactants for the first time. The probe molecules formed self-assembled nanoparticles in an aqueous solution and displayed strong aggregation-enhanced excimer emission (AEEE). During the process of surfactant monomer–micelle transition, the probe nanoparticles dissolved, and the observation of excimer–monomer emission transition clearly indicated the formation of micelles. The ratiometric changes in excimer–monomer emission (IE/IM) were used for the precise determination of critical micelle concentration (CMC) of various surfactants. The monomer–micelle transition process was directly observed under a UV lamp, and the visual determination of CMC became possible. The CMC value determination using the excimer/monomer ratio (IE/IM), UV-vis, lifetime and visual assessment clearly suggests that BzP and Cron are excellent multimode probes for monitoring the micelle structural transitions of amphiphiles. [ABSTRACT FROM AUTHOR]

Benzo[ghi]perylene and coronene were used as ratiometric fluorescent probes to monitor microenvironment changes and monomer-micelle transition for the first time. The perturbations in vibronic bands in the emission spectra of probes displayed microenvironment sensing behavior in various solvents and surfactants. The monomer–micelle transitions of anionic, cationic and neutral surfactants were monitored by changes in the ratios of vibronic band intensities. Clear CMC values were obtained, which is an advantage over the conventional probes such as pyrene with clear CMC values sometimes difficult to obtain due to less steep changes of S-shaped plots. They revealed a redshift in emission which offers a good substitute in situations where the fluorescence of pyrene and the background fluorescence of the assay mixture interfere with each other. BzP exhibited reverse behavior in the perturbations of vibronic band intensities in anionic SDS and SLS relative to cationic and non-ionic surfactants, which was not observed when pyrene was used. In addition, the vibronic band ratios of BzP are thermally more stable than those of pyrene, which is advantageous since strict assay temperature control may not be necessary. These probes are thus helpful for various applications in the areas of sensing and interface science. [ABSTRACT FROM AUTHOR]

A new fluorine–boron compound BOPHY-PTZ was designed and synthesized. The fluorescent dye was used as a highly sensitive probe for Cu2+ ion detection. The mechanism of detection involved Cu2+ ion oxidation of the phenothiazine (PTZ) moiety and blocked the intramolecular charge transfer (ICT) process from the electron-donating PTZ moiety to the electron-accepting BOPHY moiety. BOPHY-PTZ showed a weak fluorescence in solution. However, it displayed a strong fluorescence signal enhancement upon the addition of Cu2+ ions, and 1.0 nM concentration of Cu2+ can be clearly detected. The assay is simple, sensitive and convenient, and it exhibits excellent selectivity for Cu2+ ions over the other metal ions. The BOPHY-PTZ probe could be used for Cu2+ ion detection in practical samples and for environmental monitoring related applications. [ABSTRACT FROM AUTHOR]

A novel choline detection strategy is developed based on in situ polymerization of aniline on the surface of upconverting nanoparticles (UCNPs). In acidic buffer solution, aniline was protonated and attached to the surface of negatively charged UCNPs via electrostatic interactions. The in situ polymerization of aniline was initiated with the addition of a catalyst (HRP) and an oxidization agent (H2O2). The upconversion luminescence was efficiently quenched by polyaniline (PANI), and the quenching efficiency could reach 97.5%, which was higher than most of the reported organic quenchers for UCNPs. In the presence of choline oxidase, choline was hydrolyzed and produced H2O2, which caused production of polyaniline and quenching of upconversion luminescence. A sensing method for choline is thus developed. The upconversion luminescence based choline detection method can very much avoid the interference of fluorescent substances in biological samples, and also possesses the advantages of good selectivity, sensitivity and convenience. [ABSTRACT FROM AUTHOR]

A new water soluble coronene bisimide derivative (CTDI) was designed and synthesized. CTDI self-assembled in an aqueous solution and formed supramolecular nanofibers through π–π stacking and hydrophobic interactions. The nanofibers exhibit distinct peroxidase-like catalytic activity, and can catalyze the redox reaction of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide. Clear assay solution color changes were observed. The peroxidase-like catalytic property was utilized for the sensitive detection of H2O2 and glucose. The assay shows excellent sensitivity, and 1 μM of glucose could be easily detected. Glucose detection in dilute human blood samples was also demonstrated, and the results were verified using a commercial glucose meter. Our method is simple, convenient, sensitive and selective, and could facilitate the sensing of glucose in relation to biological and biomedical research applications. [ABSTRACT FROM AUTHOR]

A sensitive and selective luminescent nanoprobe (referred to as DEPN) is designed for the determination of Cu(II) ions. DEPN shows two emission peaks, one at 602 nm and caused by [Ru(bpy)], the other (peaking at 500 nm) caused by silver nanoclusters (AgNCs). The luminescence of the ruthenium complex is inert and acts as the internal reference signal, while that of the AgNCs is quenched by Cu(II) ions. Under 350 nm photoexcitation, a linear relationship is found between the ratio of emission intensity (I/I) and the concentration of Cu(II) ions in the 0.1-16 μM range. The detection limit of Cu(II) ions is estimated to be 50 nM. The DEPN was applied to the determination of Cu(II) ions in (spiked) water samples, and to intracellular imaging of Cu(II) in HeLa cells using confocal fluorescence microscopy. [ABSTRACT FROM AUTHOR]

We exploit a real-time perylene probe fluorescence turn-on method to detect acetylcholinesterase (AChE) activity through the selective decomposition of MnO2 nanosheets. The surface of the MnO2 nanosheets is negatively charged. The perylene probe (P-4C+) has four positively charged quaternary ammonium groups. When mixed together, P-4C+ attached to the surface of the MnO2 nanosheets through electrostatic attractive interactions. The fluorescence of P-4C+ was effectively quenched by the MnO2 nanosheets. Acetylthiocholine (ATCh) could be hydrolyzed to thiocholine by AChE. Thiocholine is a reducing agent. It could reduce MnO2 nanosheets to Mn2+ and thus trigger the decomposition of the MnO2 nanosheets. As a result, P-4C+ was released and the fluorescence of P-4C+ was restored. The AChE inhibitor restrained the catalytic activity of AChE and resulted in a reduced fluorescence recovery of P-4C+. Our assay method is simple and selective, with low toxicity and better biocompatibility, which would facilitate biological and biomedical applications associated with AChE activity. [ABSTRACT FROM AUTHOR]

A cancer cell specific aptamer was labeled with an aggregation-induced emission (AIE) probe for the first time. Using it as a light-up bioprobe, a specific cancer cell detection method is developed. [ABSTRACT FROM AUTHOR]

A tetracationic perylene probe (probe 1) was designed and synthesized. Probe 1 was used for the real-time fluorescence turn-on assay of alkaline phosphatase (ALP) activity and inhibitor screening. Probe 1 monomer fluorescence could be very efficiently quenched by ATP through the formation of an ATP/probe 1 complex. ALP triggered the degradation of ATP, the breakdown of the ATP/probe 1 complex, and the recovery of the probe 1 monomer fluorescence. In the presence of an ALP inhibitor, a decrease in fluorescence recovery was observed. [ABSTRACT FROM AUTHOR]

Substrate hydrolysis was utilized to trigger a “top-down” etching process for the generation of fluorescent gold nanoclusters, and the changes in emission intensity of the assay solution provide a facile way for the sensing of enzyme activity. [ABSTRACT FROM AUTHOR]

Rigid boomerang shaped triphenylamine functionalized bis-β-diketone-boron difluoride without alkyl chain and H-bonding unit exhibits good gelation ability in some mixed organic solvents directed by optimally balanced π–π interactions. [ABSTRACT FROM AUTHOR]

Correction for 'A perylene-based membrane intercalating conjugated oligoelectrolyte with efficient photodynamic antimicrobial activity' by Niu Niu et al., Chem. Commun., 2019, 55, 4395–4398. [ABSTRACT FROM AUTHOR]