Non‐invasive dynamic tracking of lysosomes and their interactions with other organelles is important for the study of lysosomal function and related diseases. However, many fluorescent dyes developed ...so far to target lysosomes cannot be used to monitor these processes due to the high concentrations required for imaging, long cell penetration times, and non‐ideal photostability. In this regard, we synthesized three lysosomal targeting probes with large Stokes shifts, good stability, and high brightness. The Q‐P‐ARh dye, developed by us for the first time, can stain lysosomes at ultra‐low concentrations (1.0 nM) without affecting the physiological functions of the lysosomes. More importantly, its excellent anti‐interference ability and ultrafast lysosomal staining ability (within 1.0 min) clearly monitored the entire dynamic process of lipophagy. Ultimately, this method can greatly contribute to the study of autophagy pathways. This novel fluorescence platform shows great promise for the development of biological probes for application in pathological environments.
A series of brand‐new large Stokes shift and highly stable fluorescent dyes were constructed. In particular, the Q‐P‐ARh fluorescent dye as a near‐infrared emission lysosomal‐specific probe with ultra‐low concentration and ultra‐fast staining characteristics for the complete lipophagy process imaging is presented.
Phototheranostics have emerged and flourished as a promising pattern for cancer theranostics owing to their precise photoinduced diagnosis and therapeutic to meet the demands of precision medicine. ...The diagnosis information and therapeutic effect are directly determined by the fluorescence imaging ability and photothermal conversion efficiency (PCE) of phototheranostic agents. Hence, how to balance the competitive radiative and nonradiative processes of phototheranostic agents is the key factor to evaluate the phototheranostic effect. Herein, molecules named ICRs with high photostaibility are rationally designed, exhibiting fluorescence emission in the second near‐infrared window (NIR‐II, 1000–1700 nm) and high PCE, which are related to the strong donor–acceptor (D–A) interaction and high reorganization energy Noteworthily, ICR‐Qu with stronger D–A interaction and a large‐sized conjugated unit encapsulated in nanoparticles exhibits high PCE (81.1%). In addition, ICR‐QuNPs are used for fluorescence imaging (FLI), photoacoustic imaging (PAI), and photothermal imaging (PTI) to guide deep‐tissue photonic hyperthermia, achieving precise removal and inhibition of breast cancer. Furthermore, combined with α‐PD‐1, ICR‐QuNPs show huge potential to be a facile and efficient tool for photo‐immunotherapy. More importantly, this study not only reports an “all‐in‐one” polymethine‐based phototheranostic agent, but also sheds light on the exploration of versatile organic molecules for future practical applications.
Polymethine dyes with second near‐infrared emission and photoacoustic imaging capability are synthesized by the electronic‐donor group regulation strategy, which demonstrates high photothermal conversion efficiency (PCE = 81.1%) as an antitumor stategy in vivo and in vitro under the multimodal imaging guidance; theoretical calculation reveals the structure regulation mechanism for the polymethine‐based phototheranostic agent to achieve an excellent PCE.
The time-varying plasma sheath surrounding a reentry spacecraft (or object) can influence the radar detection of the spacecraft seriously, causing detection error or even track loss. To study the ...influence of plasma sheath on radar detection, a time-varying plasma sheath model based on scattering matrix method is constructed. In the model, the surface media of reentry object is considered, together with some algorithm adjustments to avoid computational singularity, and the time-varying characteristics of plasma sheath are taken into account based on available measured data. By the model, the reflection coefficient of plasma sheath and the radar echo reflected by plasma-covered object are both calculated. And then a processing method of time-varying echo signal based on ambiguity function are put forward, by which the time delay and Doppler frequency of echo signal are analyzed. In the simulation, the rules of a series of time-varying parameters of plasma affecting the reflection coefficient are analyzed. Then, by ambiguity function analysis, the influence rules of plasma sheath on radar echo are revealed, accompanied by some qualitative and quantitative results. The proposed model, method, and simulation results are thought to be helpful for the radar detection of plasma-covered reentry objects.
Stretchable electrochemical sensors are conceivably a powerful technique that provides important chemical information to unravel elastic and curvilinear living body. However, no breakthrough was made ...in stretchable electrochemical device for biological detection. Herein, we synthesized Au nanotubes (NTs) with large aspect ratio to construct an effective stretchable electrochemical sensor. Interlacing network of Au NTs endows the sensor with desirable stability against mechanical deformation, and Au nanostructure provides excellent electrochemical performance and biocompatibility. This allows for the first time, real‐time electrochemical monitoring of mechanically sensitive cells on the sensor both in their stretching‐free and stretching states as well as sensing of the inner lining of blood vessels. The results demonstrate the great potential of this sensor in electrochemical detection of living body, opening a new window for stretchable electrochemical sensor in biological exploration.
Biomedical sensor: A highly controllable strategy has been developed for synthesizing Au nanotubes with a large aspect ratio. The nanotubes were used to construct an effective stretchable electrochemical sensor and to realize real‐time monitoring of mechanically sensitive cells and tissues.
In this paper, an adaptive controller design is studied for single-input–single-output (SISO) nonlinear systems with parameter uncertainties and the systems are enforced to subject to the full state ...constraints. A remarkable feature of the constrained systems is that the so-called control direction is unknown, or in other words, the signs of control gains are unknown. In the existing results, we discover that all the state constraint control results are required to determine a priori knowledge of control direction. It will be inevitable to bring about a different design procedure and a difficult task when no a priori knowledge of control direction is known. To stabilize this class of systems, two parameter adaptive controllers with Nussbaum gain technique are constructively framed to overcome the unknown control direction problem, and the novel symmetric and asymmetric Barrier Lyapunov Functions (BLFs) are adopted to guarantee that the states are not to violate their constraints. Then, the proposed BLF strategy can be to conquer the conservatism of the traditional BLF-based controls for the full state constraints. Finally, two theorems are provided to show that all the signals in the closed-loop system are bounded, the outputs are driven to follow the reference signals and all the states are ensured to remain in the predefined compact sets. The effectiveness of the proposed scheme is performed via a simulation example.
This paper concentrates upon the problem of finite-time fault-tolerant control for a class of switched nonlinear systems in lower-triangular form under arbitrary switching signals. Both loss of ...effectiveness and bias fault in actuator are taken into account. The method developed extends the traditional finite-time convergence from nonswitched lower-triangular nonlinear systems to switched version by designing appropriate controller and adaptive laws. In contrast to the previous results, it is the first time to handle the fault tolerant problem for switched system while the finite-time stability is also necessary. Meanwhile, there exist unknown internal dynamics in the switched system, which are identified by the radial basis function neural networks. It is proved that under the presented control strategy, the system output tracks the reference signal in the sense of finite-time stability. Finally, an illustrative simulation on a resistor-capacitor-inductor circuit is proposed to further demonstrate the effectiveness of the theoretical result.
In this study, an adaptive control technique is developed for a class of uncertain nonlinear parametric systems. The considered systems can be viewed as a class of nonlinear pure-feedback systems and ...the full state constraints are strictly required in the systems. One remarkable advantage is that only less adjustable parameters are used in the design. This advantage is first to take into account the pure-feedback systems with the full state constraints. The characteristics of the considered systems will lead to a difficult task for designing a stable controller. To this end, the mean value theorem is employed to transform the pure-feedback systems to a strict-feedback structure but non-affine terms still exist. For the transformed systems, a novel recursive design procedure is constructed to remove the difficulties for avoiding non-affine terms and guarantee that the full state constraints are not violated by introducing Barrier Lyapunov Function (BLF) with the error variables. Moreover, it is proved that all the signals in the closed-loop system are global uniformly bounded and the tracking error is remained in a bounded compact set. Two simulation studies are worked out to show the effectiveness of the proposed approach.
In this paper, an adaptive fuzzy optimal control design is addressed for a class of unknown nonlinear discrete-time systems. The controlled systems are in a strict-feedback frame and contain unknown ...functions and nonsymmetric dead-zone. For this class of systems, the control objective is to design a controller, which not only guarantees the stability of the systems, but achieves the optimal control performance as well. This immediately brings about the difficulties in the controller design. To this end, the fuzzy logic systems are employed to approximate the unknown functions in the systems. Based on the utility functions and the critic designs, and by applying the backsteppping design technique, a reinforcement learning algorithm is used to develop an optimal control signal. The adaptation auxiliary signal for unknown dead-zone parameters is established to compensate for the effect of nonsymmetric dead-zone on the control performance, and the updating laws are obtained based on the gradient descent rule. The stability of the control systems can be proved based on the difference Lyapunov function method. The feasibility of the proposed control approach is further demonstrated via two simulation examples.
In this paper, a framework of adaptive control for a switched nonlinear system with multiple prescribed performance bounds is established using an improved dwell time technique. Since the prescribed ...performance bounds for subsystems are different from each other, the different coordinate transformations have to be tackled when the system is transformed, which have not been encountered in some switched systems. We deal with the different coordinate transformations by finding a specific relationship between any two different coordinate transformations. To obtain a much less conservative result, in contrast to the common adaptive law, different adaptive laws are established for both active and inactive time-interval of each subsystem. The proposed controllers and switching signals guarantee that all signals appearing in the closed-loop system are bounded. Furthermore, both transient-state and steady-state performances of the switched system are obtained. Finally, the effectiveness of the developed method is verified by the application to a continuous stirred tank reactor system.
We studied the impact of risk stratification–directed interventions for minimal residual disease (MRD) on relapse and disease-free survival (DFS) prospectively in 814 subjects with standard-risk ...acute leukemia receiving allotransplantation in first or second complete remission. A total of 709 subjects were MRD− after transplantation (Group A); 105 subjects were MRD+, 49 received low-dose IL-2 (Group B), and 56 received modified donor lymphocyte infusion (DLI) with or without low-dose IL-2 (Group C). Posttransplantation immune suppression for GVHD was also modified based on MRD state. The cumulative risk of relapse was significantly less and DFS was significantly better in subjects in Group C than in subjects in Group B (P = .001 and P = .002, respectively), but was not different from subjects in Group A (P = .269 and P = .688, respectively). Multivariate analyses confirmed that MRD state and modified DLI were significantly correlated with relapse (P = .000, odds ratio OR = 0.255 and P = .000, OR = 0.269) and DFS (P = .001, OR = 0.511 and P = .006, OR = 0.436, respectively). These data suggest that risk stratification–directed interventions with modified DLI in patients with standard-risk acute leukemia who are MRD+ after transplantation may improve transplantation outcomes.
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