Explore the vast range of titles available.

A closed‐loop system that can mini‐invasively track blood glucose and intelligently treat diabetes is in great demand for modern medicine, yet it remains challenging to realize. Microneedles technologies have recently emerged as powerful tools for transdermal applications with inherent painlessness and biosafety. In this work, for the first time to the authors' knowledge, a fully integrated wearable closed‐loop system (IWCS) based on mini‐invasive microneedle platform is developed for in situ diabetic sensing and treatment. The IWCS consists of three connected modules: 1) a mesoporous microneedle‐reverse iontophoretic glucose sensor; 2) a flexible printed circuit board as integrated and control; and 3) a microneedle‐iontophoretic insulin delivery component. As the key component, mesoporous microneedles enable the painless penetration of stratum corneum, implementing subcutaneous substance exchange. The coupling with iontophoresis significantly enhances glucose extraction and insulin delivery and enables electrical control. This IWCS is demonstrated to accurately monitor glucose fluctuations, and responsively deliver insulin to regulate hyperglycemia in diabetic rat model. The painless microneedles and wearable design endows this IWCS as a highly promising platform to improve the therapies of diabetic patients. A fully integrated wearable closed‐loop system (IWCS) based on microneedle‐iontophoresis platform is developed for in situ diabetic sensing and treatment. This IWCS is demonstrated to accurately monitor glucose fluctuations and responsively deliver insulin to regulate hyperglycemia. The painless microneedles and wearable design endow this IWCS as a highly promising platform to improve the therapies of diabetic patients.

Transcranial focused ultrasound stimulation (tFUS) is an effective noninvasive treatment modality for brain disorders with high clinical potential. However, the therapeutic effects of ultrasound neuromodulation are not widely explored due to limitations in preclinical systems. The current preclinical studies are head‐fixed, anesthesia‐dependent, and acute, limiting clinical translatability. Here, this work reports a general‐purpose ultrasound neuromodulation system for chronic, closed‐loop preclinical studies in freely behaving rodents. This work uses microelectromechanical systems (MEMS) technology to design and fabricate a small and lightweight transducer capable of artifact‐free stimulation and simultaneous neural recording. Using the general‐purpose system, it can be observed that state‐dependent ultrasound neuromodulation of the prefrontal cortex increases rapid eye movement (REM) sleep and protects spatial working memory to REM sleep deprivation. The system will allow explorative studies in brain disease therapeutics and neuromodulation using ultrasound stimulation for widespread clinical adoption. This work demonstrates a chronic, artifact‐free, and closed‐loop ultrasound stimulation system based on a capacitive micromachined ultrasound transducer for neuromodulation of the medial prefrontal cortex in mice. Stimulation during non‐rapid eye movement (NREM) sleep modulates REM sleep characteristics and short‐term spatial working memory. Neuroprotective effects of REM sleep are observed, which negates the adverse effects of REM sleep deprivation in spatial working memory.

Advances in technology and improvement of efficacy for many neuromodulation applications have been achieved without understanding the relationship between the stimulation parameters and the neural activity which is generated in the nervous system. It is the neural activity that ultimately drives the therapeutic benefit and the advent of evoked compound action potential recording allows this activity to be directly measured and quantified. Closed-loop control adjusts the stimulation parameters to maintain a predetermined level of neural recruitment and has been shown to provide improved pain relief in individuals with spinal cord stimulators. However, no mechanism that relates more consistent neural recruitment to patient outcomes has been proposed. The authors propose a hypothesis that may explain the difference in efficacy between open- and closed-loop operational modes by considering the relationship between measured neural recruitment with hypothetical dose and side effect response curves. This provides a rational basis for directing clinical research and improving therapeutic systems.

An improved prescribed performance control using a backstepping technique and adaptive fuzzy is proposed for a strict feedback nonlinear dynamic system. A new virtual variable was defined to generate the virtual control that forces the tracking errors to fall within prescribed boundaries, and an adaptive fuzzy system was used to obtain required approximation performances. A strict feedback controller and adaptive laws for estimating the unknown non-linear function were designed to avoid a singularity problem and calculation of the explosive number of terms generated by the error transformations of conventional error constraint method and the recursive steps of traditional backstepping control. Lyapunov stability analysis confirmed the boundedness and convergence of the closed-loop system. The prescribed error constraint performance of the proposed control scheme was validated by applying it to control the position of a second-order non-linear system and a robot manipulator.

The paper presents a solution to the problem of synthesis of control with respect to the sliding interval length for the optimization of a class of discrete linear multidimensional objects with a quadratic performance criterion. The equation of motion of a closed multidimensional discrete system in the general non-stationary case is derived based on the length of the optimization interval and their main properties. The closed-loop is fitted with a signal representing the predicted values averaged over the whole sliding interval of optimization with a certain weight. A problem with a sliding optimization interval may not require a real-time solution by means of a sequence of solutions on compressed intervals. Therefore, the study of control systems with optimization on a sliding interval is of undoubted interest for a number of practically important control problems.

Aims/hypothesisThe aim of this work was to assess the relationship between meal nutrients and postprandial blood glucose response (PGR) in individuals with type 1 diabetes on a hybrid closed-loop system (HCLS).MethodsThe dietary composition of 1264 meals (398 breakfasts, 441 lunches and 425 dinners) was assessed by 7-day food records completed by 25 individuals with type 1 diabetes on HCLSs (12 men/13 women, mean ± SD age 40 ± 12 years, mean ± SD HbA1c 51 ± 10 mmol/mol [6.9 ± 0.2%]). For each meal, PGR (continuous glucose monitoring metrics, glucose incremental AUCs) and insulin doses (pre-meal boluses, post-meal microboluses automatically delivered by the pump and adjustment boluses) over 6 h were evaluated.ResultsBreakfast, lunch and dinner significantly differed with respect to energy and nutrient intake and insulin doses. The blood glucose postprandial profile showed an earlier peak after breakfast and a slow increase until 4 h after lunch and dinner (p < 0.001). Mean ± SD postprandial time in range (TIR) was better at breakfast (79.3 ± 22.2%) than at lunch (71.3 ± 23.9%) or dinner (70.0 ± 25.9%) (p < 0.001). Significant negative predictors of TIR at breakfast were total energy intake, per cent intake of total protein and monounsaturated fatty acids, glycaemic load and absolute amounts of cholesterol, carbohydrates and simple sugars consumed (p < 0.05 for all). No significant predictors were detected for TIR at lunch. For TIR at dinner, a significant positive predictor was the per cent intake of plant proteins, while negative predictors were glycaemic load and intake amounts of simple sugars and carbohydrate (p < 0.05 for all).Conclusions/interpretationThis study shows that nutritional factors other than the amount of carbohydrate significantly influence postprandial blood glucose control. These nutritional determinants vary between breakfast, lunch and dinner, with differing effects on postprandial blood glucose profile and insulin requirements, thus remaining a challenge to HCLSs.

Theranostics, combining therapeutic and diagnostic functions, marks a revolutionary advancement in modern medicine, with microneedle technology at its forefront. This review explores the substantial developments and multifaceted applications of microneedles, which have evolved from basic transdermal drug delivery devices to sophisticated diagnostic and therapeutic platforms. Microneedles enhance access to biomarkers via interstitial fluid, enabling real‐time monitoring of physiological conditions, such as glucose and hormone levels, thus facilitating continuous health tracking. The evolution of microneedle design from solid to dissolvable forms broadens their utility from mere drug delivery to complex sensing and therapeutic applications, including insulin delivery for diabetes management, vaccination, and gene therapy. This paper delves into the integration of microneedles with wearable technologies, highlighting their role in closed‐loop systems that combine real‐time monitoring with dynamic, precise therapeutic delivery. By addressing gaps in the literature regarding their integrated diagnostic and treatment capabilities, this review underscores the pivotal role of microneedles in personalizing medicine. It concludes with a visionary perspective on the future trajectory of microneedle technology, emphasizing its potential to revolutionize therapeutic strategies through enhanced efficacy, safety, and patient compliance. The TOC figure illustrates the revolutionary role of microneedles in modern medicine, showcasing their dual diagnostic and therapeutic functions. On the left, microneedles access interstitial fluid for real‐time monitoring of biomarkers like glucose and hormones. On the right, their therapeutic applications include drug delivery, diabetes management, and gene therapy, highlighting their integration into wearable systems for personalized medicine.

This research aimed to quantify the impact of low dose of esketamine on BIS and validate the feasibility of closed-loop TCI system based on the new BIS baseline with low dose of esketamine. This study consisted of two phases. The first phase was to quantify the impact of a low dose of esketamine (0.2mg kg bolus, 5μg kg min infusion for 30min) on BIS and establish a new BIS baseline for propofol-remifentanil general anesthesia. The second phase was used to validate the feasibility of closed-loop TCI system based on the new BIS baseline. One hundred and eleven patients were randomly and equally assigned to three groups (group A: adjusted group, group N: non-adjusted group and group C: control group). After administering a low dose of esketamine, group A adjusted drug dosage based on new BIS baseline, while group N based on the original BIS baseline of 50, group C adjusted drug doses based on the original baseline of 50 without esketamine. Main outcome was controller performance (% time within±10units of the BIS setpoint). Secondary outcomes were drug consumption, occurrence of adverse events such as intraoperative awareness, treatment of hemodynamic changes and postoperative recovery quality. In the first phase, after administering a low dose of esketamine, the BIS increased from 49.9±4.5 to 59.6±6.0, <0.01. In the second phase, the controller performance in group A and N were within the range of high-performance systems, and both were equivalent with control group. Group A showed lower consumption of propofol compared to control group (5.58±1.12 vs 6.69±1.36 (mg·kg ·h ), <0.05). There was no difference in adverse events such as intraoperative awareness, recovery assessment and postoperative VAS, PONV and shivering, QoR-15 assessment after adjusting the BIS baseline. It is feasible to operate the closed-loop TCI system based on the adjusted BIS baseline in the presence of low dose of esketamine.

The design of output constrained control system for unmanned aerial vehicles deployed in confined areas is an important issue in practice and not taken into account in many autopilot systems. In this study, the authors address a neural networks-based adaptive trajectory tracking control algorithm for multi-rotors systems in the presence of various uncertainties in their dynamics. Given any sufficient smooth and bounded reference trajectory input, the proposed algorithm achieves that (i) the system output (Euclidean position) tracking error converges to a neighbourhood of zero and furthermore (ii) the system output remains uniformly in a prescribed set. Instead of element-wise estimation, a norm estimation approach of unknown weight vectors is incorporated into the control system design to relieve the onboard computation burden. The convergence property of the closed-loop system subject to output constraint is analysed via a symmetric barrier Lyapunov function augmented with several quadratic terms. Simulation results are demonstrated on a quadrotor model to validate the effectiveness of the proposed algorithm.

Low frequency oscillation occurs frequently in the smart grid, which threatens the security and stability of the physical system. Wide-area damping controller (WADC), which belongs to cyber system, can effectively suppress inter-area low frequency oscillations and improve the small signal stability of the closed-loop cyber-physical system (CPS). However, with the introduction of global signals, time delays of communication are inevitable. Considering that, this paper deduces the general mathematics expression among electromagnetic torque coefficients, WADC control parameters and time delays, which makes it possible to analyse the influence mechanism of time delay on small signal stability. Based on these analysis, on the one hand, the time-delay small signal stability region is established to evaluate the operation state of closed-loop CPS, on the other hand, if small signal stability is not achieved due to the measured time delays, optimisation scheme is proposed to carry out WADC control parameters coordination to optimise small signal stability of the closed-loop system. Finally, taking two time delays as example, this study verifies the effectiveness and advantages of the proposed method by comparing the closed-loop system performance considering two time delays with the cases of considering singe time delay and without time delay.