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Photodynamic therapy (PDT) could induce apoptosis by releasing reactive oxygen species (ROS) to treat tumor. Application of pH/light dual-activated nanoparticles could generate ROS in the acidic tumor microenvironment under 808 nm laser irradiation for precise treatment. L-arginine (L-Arg) triggered by ROS is an efficient nitric oxide (NO) donor for gas therapy. In addition, it is reported that peroxynitrite (ONOO-) produced by rapid reaction of ROS and NO could sensitize PDT and induce apoptosis for synergistic treatment. Herein, we developed the L-Arg loaded pH/light dual-activated PEGylated photosensitizer for self-assembly into nanoparticles named Rho-Arg. As measured by fluorescence spectroscopy, the pKa of Rho-Arg was 5.5, which is suitable for applying in the tumor microenvironment. The nanoplatform was firstly activated under the acidic condition of tumor, and then illuminated by 808 nm laser to controllably release ROS, and sequentially produced NO and ONOO-. In conclusion, the Rho-Arg nanoplatform may provide a promising synergistic therapy tool for tumor treatment. • "Dual lock" control enables effective precision treatment. • An excellent nitric oxide donor. • Photodynamic therapy combined with gas therapy for tumor suppression. • Quickly generate ONOO- sensitized photodynamic therapy. [ABSTRACT FROM AUTHOR]

We report a mitochondria-targeted near-infrared probe (NRh-O) for frequency upconversion luminescence (FUCL) imaging of hypoxia. Under hypoxic conditions, NRh-O rapidly responds to release the FUCL product NRh (λex/em = 850/825 nm) with high sensitivity and selectivity in mitochondria. This highlights the potential application of a hypoxia-responsive probe in early clinical diagnosis. [ABSTRACT FROM AUTHOR]

The antibiotic therapy usually leads to the bacterial resistance, and the traditional photosensitizer was in "always on" state with damage to normal tissue. Fortunately, the activatable near-infrared photosensitizer has a high depth of tissue penetration, and can be specifically released with low side effect. Therefore, we designed and synthesized a penicillin G acylase (PGA) activable photosensitizer (NFh-PGA), which could be activated to produce NFh-OH. NFh-OH can product singlet oxygen (1O 2) under near-infrared light 730 nm excitation, and have an excellent antibacterial effect in vitro and in vivo. The probe accelerates the healing of bacterial infection wounds by near-infrared imaging guiding PDT. This work provides a strategy for the integrated design of diagnosis and treatment of bacterial infection. [Display omitted] ● A novel activable photosensitizer (NFh-PGA) by PGA was developed. ● The fluorescence and phototherapeutic ability of the probe kept the OFF state in the normal physiological environment. ● The NFh-PGA could be specifically activated and efficiently generating singlet oxygen (1O 2) under 730 nm laser. ● The NFh-PGA played an excellent bactericidal effect and accelerated the healing speed of infected wounds. [ABSTRACT FROM AUTHOR]

Carboxylesterase (CE) localized in the lumen of the endoplasmic reticulum (ER) hydrolyzes many prodrugs to exert therapeutic effect, such as anticoagulant clopidogrel and anticarcinogen irinotecan. Diabetes might induce CE to show a decreasing level, and thus impact the therapy effect. Hence, it is crucial to monitor the change of CE in treatment for diabetes for using drug rationally. We attempted to develop novel near-infrared fluorescent probes to detect CE activity in the ER with high selectivity and sensitivity in cells and in vivo , and help to guide the use of CE-related medications. Moreover, the excellent chemodosimeter (Hecy-1) could be applied in detecting CE level in tumor cells and LO2 cells. In glucose-induced CE changes of LO2 cells, Hecy-1 still showed admirable imaging ability. This research may further promote the study of intracellular fine biological activities of CE and the development of diabetes diagnosis. [Display omitted] • Hecy-1 could accurately distinguish carboxylesterase with excellent selectivity and sensitivity. • The probe could detect carboxylesterase level in diabetes group and treatment group for therapy effect. • A platform may further promote the study of intracellular biological activities and diabetes diagnosis. [ABSTRACT FROM AUTHOR]

This paper studies the synchronization problem for mobile cellular device-to-device (D2D) networks. Depending on the number of devices that are in coverage of the base station, the D2D environment can be divided into three categories where the partial-coverage and out-of-coverage are challenging scenarios and thus are the focus of this paper. First, we discuss five main challenges imposed on the synchronization problem in mobile D2D networks. More specifically, there are different challenges in the two coverage scenarios, since they do not have exactly the same synchronization objectives. Second, we propose a low-complexity Adaptive distRibuted nEtwork Synchronization (ARES) algorithm to address the five challenges. The design principles and the theories behind the ARES scheme are also analyzed in detail. Finally, we provide comprehensive simulations to evaluate different synchronization schemes, where the proposed ARES mechanism shows very promising performance. [ABSTRACT FROM AUTHOR]

Direct device-to-device (D2D) links are proposed as a possible enabler for vehicle-to-vehicle (V2V) communications, where the incurred intracell interference and the stringent latency and reliability requirements are challenging issues. In this paper, we investigate the radio resource management problem for D2D-based V2V communication. First, we analyze and transform the latency and reliability requirements of V2V communication into optimization constraints that are computable using only the slowly varying channel information. This transformation opens up the possibility of extending certain existing D2D techniques to cater to V2V communication. Second, we propose a problem formulation that fulfills the different requirements of V2V communication and traditional cellular communication. Moreover, a Separate resOurce bLock and powEr allocatioN (SOLEN) algorithm is proposed to solve this problem. Finally, simulations are presented to evaluate different schemes, which illustrate the necessity of careful design when extending D2D methods to V2V communication, as well as show promising performance of the proposed SOLEN algorithm. [ABSTRACT FROM AUTHOR]

Aiming to the disadvantages of short-term load forecasting with empirical mode decomposition (EMD) such as mode mixing and many high-frequency random components, a new short-term load forecasting model based on ensemble empirical mode decomposition (EEMD) and sub-section particle swarm optimization (SS-PSO) is proposed in this paper. Firstly, the load sequence is decomposed into a limited number of intrinsic mode function (IMF) components and one remainder by EEMD, which can avoid the mode mixing problem of traditional EMD. Then, through calculating and observing the spectrum of decomposed series, some low-frequency IMFs are extracted and reconstructed. Other IMFs can be forecasted with appropriate forecasting models. Since IMF1 is main random component of the load sequence, the linear combination model is adopted to forecast IMF1. Because the weights of the linear combination model are very important to obtain high forecasting accuracy, SS-PSO is proposed and used to optimize the linear combination weights. In addition, the factors such as temperature and weekday are taken into consideration for short-term load forecasting. Simulation results show that accuracy of the load forecasting model proposed in the paper is higher than that of BP neural network, RBF neural network, support vector machine, EMD and their combinations. [ABSTRACT FROM AUTHOR]

As the organs responsible for toxin transformation and excretion in the body, damage to the liver and kidneys induced by inevitable drug toxicity is the main cause of acute liver and kidney injury. P-Acetamidophenol overdose leads hypochlorous acid (HClO) to accumulate in the mitochondria of tissues, ultimately resulting in acute liver and kidney injury in humans, despite its clinical use as an antipyretic medicine. Herein, we report an HClO-activatable self-assembling ratiometric nanoprobe NRH-800-PEG for screening the upregulation of HClO by colocalization in mitochondria while monitoring the changes in the endogenous HClO levels in cells with ratiometric signals. Furthermore, NRH-800-PEG was constructed to evaluate injury by fluorescence ratio imaging in the tissues of inflammatory mice. Our strategy offers a novel tool for assessing disease progression during drug-induced liver and kidney injury. [ABSTRACT FROM AUTHOR]

Increasing interest has been noted in photosensitizer design. Currently, most small molecular photosensitizers have several drawbacks, including limited penetration depth and unsatisfying photostability. For addressing these limitations, Frequency upconversion luminescence (FUCL) small molecule was adopted as a photosensitizer design strategy for its deeper penetration, sensitive imaging, and better photostability. We developed a series of FUCL (NIR-NH 2 , NIR-NHEt, NIR-NEt 2) molecules with rigid structures. Equipped with the most powerful electron donor, NIR-NEt 2 exhibits the highest singlet oxygen generation, the strongest upconversion luminescence intensity under 808 nm irradiation and mitochondria-targeted ability. FUCL can be a superior molecular platform for image-guided photodynamic therapy of cancer cells. We developed a series of mitochondria-targeted small FUCL molecules (NIR-NH 2 , NIR-NHEt, and NIR-NEt 2) with different electron-donating segments and screened for the most outstanding one, NIR-NEt 2 , applied for the photodynamic therapy of cancer cells, which demonstrating a new molecular platform for deep-seated upconversion photodynamic therapy. [Display omitted] • FUCL is a one-photon process with advantages of deeper penetration, higher signal-to-noise ratio, and more excellent photostability over the traditional down-conversion luminescence. • NIR-NEt 2 was screened from a series of frequency upconversion luminescence molecules for the excellent photostability, best FUCL ability and ROS generation. • The tactic of heavy-atom free of FUCL PSs that modify strong donating groups on the electron-donating part of D-A structure was investigated. [ABSTRACT FROM AUTHOR]

Phototherapy has developed as a powerful method for remedial modalities. The conventional photosensitizers are "always on" state and lack tumor targeting, which contributed to poor therapeutic effect and high toxicity. Therefore, we developed an aspartyl aminopeptidase (DNPEP) activated self-assembled organic nanoparticles (NRh-Asp NPs) with sensitive external irradiation-induced photothermal therapy and photodynamic therapy (PTT/PDT). NRh-Asp NPs can be activated to NRh–NH 2 NPs by DNPEP, demonstrating strong near-infrared (NIR) fluorescence, and efficiently generating heat and singlet oxygen under the near-infrared laser. NRh-Asp NPs was successfully used for visualizing DNPEP in vitro and in vivo in NIR region, and demonstrated good synergistic anti-cancer efficacy of PDT and PTT. These results suggest that DNPEP-mediated NRh-Asp NPs are promising candidates for image-guided phototherapeutic of tumor. [Display omitted] • A novel self-assembled fluorescent probe (NRh-Asp NPs) was developed for detecting DNPEP activity and phototherapeutic therapy of tumor. • The NRh-Asp NPs exhibited high selectivity/sensitivity for DNPEP analysis with NIR fluorescent. • The fluorescence and phototherapeutic ability (PTT and PDT) of NRh-Asp NPs kept only the ON state in the tumor microenvironment. • The NRh-Asp NPs can effectively inhibit tumor growth by synergistic effects of PTT and PDT without causing damage to other organs. [ABSTRACT FROM AUTHOR]

Abstract: A series of hyperbranched polyimides were successfully synthesized by A2+B2B′+B2 copolymerization from 2,2-bis(3,4-dicarboxylphenyl) hexafluoropropane dianhydride (6FDA), 2,4,6-triaminopyrimidine (TAP) and 4,4′-oxydianiline (ODA). Self-standing polyimides membranes with sufficient mechanical properties were achieved by incorporation of difunctional B2 comonomer into the hyperbranched polymer structure. The degree of branching was estimated using 1H NMR spectroscopy. The morphology structure of the prepared polyimides was evaluated by wide-angle X-ray diffraction patterns, and the d-spacing values first increased gradually to the highest value 5.73Å with increasing the content of TAP, and then decreased. The densities of these films were tested and the difference in density is probably due to the different inter-macromolecular packing efficiency. Both the 5% weight loss at temperatures and the glass transition temperatures (Tg) of the obtained polyimides decreased with decreasing the content of ODA comonomer. Similar tendency was found for tensile strength and elongation at break. Gas transport measurements showed the prepared TAP–ODA–6FDA hyperbranched polyimides exhibited lower permeabilities compared with ODA–6FDA linear polyimides, but higher O2/N2 and CO2/N2 selectivities. So they are expected to apply in the field of gas separation. [Copyright &y& Elsevier]

This paper aims to develop a load forecasting method for short-term load forecasting based on multiwavelet transform and multiple neural networks. Firstly, a variable weight combination load forecasting model for power load is proposed and discussed. Secondly, the training data are extracted from power load data through multiwavelet transform. Lastly, the obtained data are trained through a variable weight combination model. BP network, RBF network and wavelet neural network are adopted as the training network, and the trained data from three neural networks are input to a three-layer feedforward neural network for the load forecasting. Simulation results show that accuracy of the combination load forecasting model proposed in the paper is higher than any one single network model and the combination forecast model of three neural networks without preprocessing method of multiwavelet transform. [ABSTRACT FROM AUTHOR]

A series of novel soluble polyimides was synthesized from commercially available 2,4,6-triaminopyrimidine (TAP), 2,2-bis(3,4-dicarboxylphenyl) hexafluoropropane dianhydride (6FDA), α,ω-aminopropylpoly(dimethylsiloxane) and 1,3-bis(3-aminophenoxy)benzene. TAP is the branched monomer, and polymerization process had been improved in three ways by using TAP to prepare soluble polyimides. The polyimides were characterized by Fourier transform infrared spectra, proton nuclear magnetic resonance, ultraviolet–visible spectrometer analysis, wide-angle X-ray diffraction, and size-exclusion chromatography with multiangle laser light-scattering detection. The branched polyimides showed excellent solubility both in strong polar solvents and in common low-boiling point solvents. Differential scanning calorimetric and thermogravimetric analyses showed high glass transition temperatures and excellent thermal stability for branched polyimides with moderate content of TAP. Polyimide membranes were formed at relatively low temperature, and the mechanical properties were tested. These results ensure that soluble polyimides with moderate content of TAP showed outstanding combined features and are desirable candidate materials for advanced applications. [ABSTRACT FROM AUTHOR]

Acetylcholinesterase (AChE) plays an important role in the process of chemotherapy drug-induced cell apoptosis and is also an apoptosis marker to diagnose disease and assay the effect of the drug. Thus, we designed and synthesized a novel near-infrared fluorescent probe (NFL-SF) to detect AChE activity, which contained near-infrared (NIR) fluorophore NFL-OH and 2-thienylformyl chloride as the recognition unit. The probe has higher specificity and sensitivity to AChE and excellent biocompatibility. With the increasing concentration of AChE, the probe displayed an enhanced fluorescence signal at 745 nm for 30 min, with the detection limit of 0.2 mU/mL. In addition, NFL-SF not only detected exogenous AChE activity, but also effectively monitored the endogenous AChE activity of chemotherapeutic drug-induced cell apoptosis in living cells. When the AChE activity was inhibited with donepezil, the fluorescence intensity of the NIR channel was significantly reduced. Notably, the probe was successfully applied to in vivo imaging of nude mice. We believe that this probe could provide a strategy for rapidly and visually monitoring AChE activity. • A novel AChE near-infrared fluorescent probe was designed based on the PET. • The probe has excellent selectivity and sensitivity towards AChE. • The probe NFL-SF could effectively monitor AChE activity in vitro and in vivo chemotherapeutic drugs-induced cell apoptosis. [ABSTRACT FROM AUTHOR]

Silicon (Si)-containing polyimides (PIs) with superior atomic oxygen (AO) resistance are promising materials for space applications. Here, in this study, we present the synthesis and characterization of eight Si-containing PI thin films and evaluate their AO durability. The resulting PI films exhibited high thermal stability and preferable AO resistance but showed slightly reduced mechanical performance relative to pristine PI. The highest optical transparency at 550 nm was observed for PI/octaaminopropylsilsesquioxane, while the lowest value was observed for PI/silica (SiO2) hybrids. X-Ray photoelectron spectroscopic study suggested that the topmost surface of PI was degraded at the early stage and an SiO2 inert protective layer was finally formed on the surface of hybrid films after AO exposure. It is found that Si-containing units of higher oxidation states and with higher Si/O molar ratio are favorable to improve the AO resistance. Dispersion of Si at molecular level contributes to improving anti-AO property as well as optical transparency of the prepared films. The characterization of scanning electron microscopy indicated a continuous SiO2 protective layer was crucial to prevent AO from eroding the bulk matrix. [ABSTRACT FROM AUTHOR]

[Display omitted] • NO chemically caged in rhodamine-containing frequency upconversion luminescence (FUCL) dyes. • NO prodrug PEG-Bn-NO exhibited excellent spatiotemporal uncaging controllability upon direct near-infrared light activation. • Immediate and precise exposure of cancer cell to NO was achieved for efficient gas therapy. • Highly sensitive FUCL readout offered deep-tissue tumor imaging while confirming accurate drug delivery. Gas therapy has emerged as an effective cancer treatment for minimal tissue invasiveness and little drug resistance. Particularly, Nitric oxide (NO) gas transmitter has drawn extensive attention for direct cancer-killing efficiency at high concentrations. However, the major drawbacks of the current NO prodrugs are insufficient NO delivery to the target tissues and lack the ability of spatiotemporal release precision. Meanwhile, it is also underestimated for NO prodrugs to achieve real-time deep-tissue drug monitoring visualization with high sensitivity for reliable delivery confirmation. Herein, two near infrared (NIR) light-triggered NO-releasing donors (NRh-Bn-NO and NRh-Et-NO) are synthesized for NO delivery with superb spatiotemporal controllability while tracing drug release mediated by frequency upconversion luminescence (FUCL) readout. FUCL is a unique anti-Stokes luminescence imaging modality that provides superior imaging sensitivity and increased signal-to-noise ratio for high resolution, which takes precedence in deep-seated tumor imaging. Furthermore, a nano-system (PEG-Bn-NO) is constructed with NRh-Bn-NO to guarantee efficient NO generation by direct NIR activation while allowing high-resolution drug monitoring in depth. Following intravenous administration, PEG-Bn-NO is specifically targeted to the tumor site and selectively controlled tumor growth induced by NIR light. The NO nano-prodrug should be inspirational to highly efficient gas therapy integrated with real-time drug delivery monitoring. [ABSTRACT FROM AUTHOR]