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Antitumor agents often lack effective penetration and accumulation to achieve high therapeutic efficacy in treating solid tumors. Nanomotor-based nanomaterials offer a potential solution to address this obstacle. Among them, nitric oxide (NO) based nanomotors have garnered attention for their potential applications in nanomedicine. However, there widespread clinical adoption has been hindered by their complex preparation processes. To address this limitation, we have developed a NO-driven nanomotor utilizing a convenient and scalable nanogel preparation procedure. These nanomotors, loaded with the fluorescent probe / sonosensitizer chlorin e6 (Ce6), were specifically engineered for sonodynamic therapy. Through comprehensive in vitro investigations using both 2D and 3D cell models, as well as in vivo analysis of Ce6 fluorescent signal distribution in solid tumor models, we observed that the self-propulsion of these nanomotors significantly enhances cellular uptake and tumor penetration, particularly in solid tumors. This phenomenon enables efficient access to challenging tumor regions and, in some cases, results in complete tumor coverage. Notably, our nanomotors have demonstrated long-term in vivo biosafety. This study presents an effective approach to enhancing drug penetration and improving therapeutic efficacy in tumor treatment, with potential clinical relevance for future applications. [Display omitted] • To overcome tissue barriers, biodegradable nanogels were engineered into nanomotors by incorporating L-arginine and Ce6. • Tissue penetration and accumulation were meticulously analyzed and evaluated using 2D/3D cell cultures and in vivo mouse models. • A combination therapy was developed, demonstrating improved therapeutic efficacy and long-term biosafety in vivo. [ABSTRACT FROM AUTHOR]

In recent years, biosyncretic robots, a novel type of robot that integrates living and artificial materials, have gained significant attention. Biosyncretic robots are expected to leverage the advantages provided by living materials and offer a new approach to address the challenges faced by traditional robots, such as biocompatibility, intrinsic safety, and miniaturization. Therefore, this review aims to provide an overview of the current state of development of biosyncretic robots. First, the existing research on biosyncretic robots based on commonly used living materials is systematically categorized and introduced, including cardiomyocytes, skeletal muscle cells, insect dorsal vascular tissue, and microorganisms. Subsequently, their potential in the fields of in vivo medical diagnosis and treatment, organ‐on‐a‐chip, tissue engineering, environmental monitoring, and postdisaster rescue in detail is also discussed. Finally, the current challenges faced by biosyncretic robotic research, including establishing theoretical models, fabrication, cultivation, and maintenance of living materials, controllability, versatility, artificial material, and entering the human body or leaving the laboratory, are examined. This review summarizes the cutting‐edge progress of biosyncretic robots and provides insights into their future development. [ABSTRACT FROM AUTHOR]

This work presents a hassle-free rheological assessment of fluidic media using the frequency response of a self-sensing and self-actuating piezoelectric cantilever sensor. Firstly, an analytical modelling approach for a unimorph-based cantilever sensor is derived and validated. Afterwards, the sensing performance of a rectangular cantilever sensor is improved by modifying its profile to a stepped shape. Frequency response parameters of the cantilever sensors are tracked in vacuum as well as in water, glycerin and varying concentration glycerin solution. These parameters are used to develop the calibration curves for the density and viscosity assessment of the water-glycerin solutions. The calculated density and viscosity utilizing the cantilever sensors are in good agreement with the respective values given by the standard instruments. This implies that the presented sensors can be successfully used for density and viscosity measurement of range 1000–1270 kg/m3 and 12.82–41.35 cP, respectively. The presented method is capable to simultaneously estimate the density and viscosity of the fluidic media without fully immersing the sensor in that media, which can tackle many operational troubles. [ABSTRACT FROM AUTHOR]

One of the modern methods for enhancing the efficiency of photovoltaic (PV) systems is implementing a solar tracking mechanism in order to redirect PV modules toward the sun throughout the day. However, the use of solar trackers increases the system's electrical consumption, hindering its net generated energy. In this study, a novel self-tracking solar-driven PV system is proposed. The smart solar-driven thermomechanical actuator takes advantage of a solar heat collector (SHC) device, in the form of a parabolic trough solar concentrator (PTC), and smart shape memory alloy (SMA) to produce effective mechanical energy for solar tracking applications from sun rays. Furthermore, a thermal–optical analysis is presented to evaluate the performance of the solar concentrator for the simulated weather condition of Dammam City, Saudi Arabia. The numerical results of the thermal and optical analyses show the promising feasibility of the proposed system in which SMA springs with an activation temperature between 31.09 °C and 45.15 °C can be utilized for the self-tracking operations. The work presented adds to the body of knowledge an advanced SMA-based SHC device for solar-based self-actuation systems, which enables further expansions within modern and advanced solar thermal applications. [ABSTRACT FROM AUTHOR]

As a research field of robotics, micro/nanorobots have been extensively studied in recent years because of their important application prospects in biomedical fields, such as medical diagnosis, nanoscale surgery, and targeted therapy. In this article, recent progress on micro/nanorobots is reviewed regarding actuation technologies. First, the different actuation mechanisms are divided into two types, external field actuation and self-actuation. Then, a few latest achievements on actuation methods are presented. On this basis, the principles of various actuation methods and their limitations are also analyzed. Finally, some key challenges in the development of micro/nanorobots are summarized and the next development direction of the field is explored.

The art of paper folding also known as Origami plays an important role in various research areas of different scientific fields. Origami structures possess many useful characteristics such as reconfigurability, flexibility, deployability, compactness, and multi-functionality. These attributes are inevitable for modern communication systems. Additionally, they provide antenna engineers an extra degree of freedom while blueprinting next-generation designs. One of the desirable features of origami is its folding capability. Using this property, it can be transformed into a two-Dimensional (2D) sheet from a three-Dimensional (3D) structure and vice versa through external stimulus. In recent years, researchers have proposed numerous smart materials to optimize folding behavior. These smart materials extend the functionality of origami technology for designing self-folding structures required in space systems, small scale devices, and self-assembly systems. Origami structures feature many useful characteristics pertinent to modern day design challenges of communication systems such as reconfiguration, flexibility, compactness, and multifunctionality. In this work, a state of the art review is presented on conceptualization, design challenges, and fabrication of light-weight and low-cost deployable origami antennas. Furthermore, to provide critical insights deployment challenges and possible solutions are also provided. It is believed that this work will not only help peers to understand the basic working principles of different origami structures but will also lay the foundation for future research in the evolving field of origami-based antennas. Moreover, the design methodology proposed in this paper will also provide pragmatic solutions for origami antennas suitable for the harsh and rigid environments.

We introduce a new mechanism for self‐actuating deployable structures, based on printing a dense pattern of closely‐spaced plastic ribbons on sheets of pre‐stretched elastic fabric. We leverage two shape‐changing effects that occur when such an assembly is printed and allowed to relax: first, the incompressible plastic ribbons frustrate the contraction of the fabric back to its rest state, forcing residual strain in the fabric and creating intrinsic curvature. Second, the differential compression at the interface between the plastic and fabric layers yields a bilayer effect in the direction of the ribbons, making each ribbon buckle into an arc at equilibrium state and creating extrinsic curvature. We describe an inverse design tool to fabricate low‐cost, lightweight prototypes of freeform surfaces using the controllable directional distortion and curvature offered by this mechanism. The core of our method is a parameterization algorithm that bounds surface distortions along and across principal curvature directions, along with a pattern synthesis algorithm that covers a surface with ribbons to match the target distortions and curvature given by the aforementioned parameterization. We demonstrate the flexibility and accuracy of our method by fabricating and measuring a variety of surfaces, including nearly‐developable surfaces as well as surfaces with positive and negative mean curvature, which we achieve thanks to a simple hardware setup that allows printing on both sides of the fabric. [ABSTRACT FROM AUTHOR]

Transformational advances in additive manufacturing combined with the unique functional behavior of shape memory alloys (SMAs) has propelled the field of 4D printing “smart” materials. In this study, we leverage multiple processing pathways with additive manufacturing to design and fabricate SMA components capable of precise, self-guided shape change that could actuate large-scale (up to 25 × 25 × 33 cm3) structures under external thermal stimuli. The dual benefits of minor alloy doping (

This article reports investigation of self-actuation in phase change material (PCM) germanium telluride (GeTe)-based radio frequency (RF) switches as a limitation to RF power handling. PCM switches are fabricated in-house with multiple design dimensions for evaluation and testing under various RF power levels. RF power handling capability and maximum dc current carrying capacity in the ON-state of the switches is studied for four different device layouts. Self-actuation in the OFF-state is reported at varying input RF power and dc voltage levels. A tradeoff between RF power handling capacity and device performance is discussed, establishing a correlation between design parameters and the power handling. The improved PCM switches exhibit a record high continuous wave (CW) RF power handling capability ranging from +35.5 to +39.2 dBm. [ABSTRACT FROM AUTHOR]

Solid‐state cooling fibers comprising an electrocaloric polymer, poly(vinylidene fluoride‐trifluoroethylene‐chlorofluoroethylene) terpolymer, spray‐coated on a conductive fiber core electrode, and a coaxially coated single‐walled carbon nanotubes outer electrode are reported. The fiber coolers can be less than 160 µm thin and more than 8 cm long. Measured cooling ΔT of the EC fibers is 0.7 °C at an electric field of 100 V µm−1 applied between the electrodes. The fiber coolers are flexible; 2000 cycles of repeated bending to a 2.5 mm curvature radius do not significantly degrade the cooling ΔT. Self‐actuated bending of the fibers is observed during the EC operation, which allows the EC fibers to move heat from one location to another without any additional driving mechanisms such as electromagnetic motors, pumps, or electrostatic actuation that are commonly used in conventional coolers. The self‐actuating EC fibers represent the first ever active cooler in a thin fiber form factor. [ABSTRACT FROM AUTHOR]

Providing a cheaper and comfortable solution in the rehabilitation process of stroke patients to improve their hand function is a challenging task. Employing physiotherapists to improve hand function of stroke patients once they are discharged from the hospital is a costly affair in developing and underdeveloped nations. In this research work the design, development and control of a low cost, self-actuated hand orthotic device was presented that can be used in the rehabilitation process of stroke patients in improving their hand functions. In this paper a single degree of freedom, low cost, easy to wear, easy control, auto-actuating orthosis was designed on the basis of the abduction and adduction method. A graphical user interface (GUI) was developed for self-actuation and it would simplify the control of the device to alter the angle and speed of the carpometacarpal joint during the therapy of stroke and surgery sufferers by the physiotherapists at hospitals. The same can be employed by users post hospital treatment at their residences without the need to hire physiotherapists. The experiments conducted in the lab and tests with patients at the rehabilitation center demonstrate the success of the system. Given its excellent comfortableness, easy-of-use, light-weight and affordable cost, this device can be used to address the rehabilitation issues of the patients with hand paralysis, particularly in developing countries post hospital treatment. [ABSTRACT FROM AUTHOR]

Abstract Shape memory polymers (SMPs) are a polymeric smart material that can register two or more temporary shapes and transform to one another through an external stimulus. Despite their compactness and customizability, SMPs haven't been able to be adopted for mainstream applications. Since the majority of SMPs are triggered by heat, and SMPs have a very poor thermal conductivity, large thermal gradients within the polymer appear which cause slow response, inhomogeneous heat distribution and thus non-uniform transformation of shapes and cracks. Many have attempted to improve their thermal performance through the incorporation of filler-based nanomaterials. However, the outcome is ineffective as the spatial dispersion of fillers within the SMP is inhomogeneous and leads to performance loss. Contrastingly, the herein presented new class of nanocomposite-SMP, composed by 3D-foam fillers, showcase a much more efficient SMP adaptable to larger area with faster transformation speed and without any performance loss. Furthermore, the improved thermal properties lead to a decrease in required input energy, as well as render the SMP a self-heating capability which can be further designed into timed multi-step SMP behavior. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Given the great importance of creativity in society, and in health psychology in particular, investigating how creativity can be enhanced is a valuable area of research. Interventions that enable individuals to become more creative vary in their focus from increasing divergent thinking to task reactivation during sleep. This article introduces psychosynthesis psychology as an additional theoretical and therapeutic approach for enhancing creativity through its concept that creativity originates from different levels of the unconscious. We show that the subpersonality model, one of the fundamental psychosynthesis techniques, is an effective intervention for aiding creative expression as it helps people connect to different levels of their unconscious creativity. It is assumed that through the use of this technique, clients are able to release and unblock energies that not only allow them to rebuild their personal identities but also become actively creative in their daily lives. We support this assumption with qualitative findings that include testimonies from eleven clients in The Netherlands who received psychosynthesis counseling. In addition, qualitative data of a case study demonstrates subpersonality integration and its role in helping clients to become more creative in their personal and professional lives. The present article is, to the best of our knowledge, the first to demonstrate the beneficial effects of using psychosynthesis to facilitate creativity. The framework of psychosynthesis psychology, its techniques (which include the subpersonality model), and its therapeutic approach are viable methodologies for anyone searching to unblock and activate new creative energy and achieve personal and professional growth. [ABSTRACT FROM AUTHOR]

The self-actuating and self-sensing cantilevers make it possible to perform precise non-contact atomic force microscopy (AFM) surface investigations. The measurement and control precision in the bandwidth of up to 2 MHz is ensured by integration of the most important microscope components: the tip deflection actuator and the tip deflection detector with the spring beam. In this way the vast majority of the parasitic disturbances like resonances of a bulk piezoactuator used for the cantilever excitation are eliminated. In this paper we describe thermomechanical and electromagnetic technologies for the actuation of the cantilever vibration whose oscillation is detected using the piezoresistive deflection sensor. We present how to control the cantilever mechanics using both actuation methods. We discuss the differences in power consumption when the cantilever is actuated and what are the surface scanning features of both technologies. We show that an atomic force microscope is capable of retaining its imaging speed and resolution when its cantilever is actuated in the thermomechanical and electromagnetic way. The obtained results illustrate that the selection of the proper actuation method extends applicability of the proposed AFM technologies. [ABSTRACT FROM AUTHOR]

The hydrodynamic characteristics of hybrid fluid made of liquid metal/aqueous solution are elementary in the design and operation of conductive flow in a variety of newly emerging areas such as chip cooling, soft robot, and biomedical practices. In terms of physical and chemical properties, such as density, thermal conductivity and electrical conductivity, their huge differences between the two fluidic phases remain a big challenge for analyzing the hybrid flow behaviors. Besides, the liquid metal immersed in the solution can move and deform when administrated with non-contact electromagnetic force, or even induced by redox reaction, which is entirely different from the cases of conventional contact force. Owing to its remarkable capability in flow and deformation, liquid metal immersed in the solution is apt to deform on an extremely large scale, resulting in marked changes on its boundary and interface. However, the working mechanisms of the movement and deformation of liquid metal lack appropriate models to describe such scientific issues via a set of well-established unified equations. To promote investigations in this important area, the present paper is dedicated to summarizing this unconventional hydrodynamics from experiment, theory, and simulation. Typical experimental phenomena and basic working mechanisms are illustrated, followed by the movement and deformation theories to explain these phenomena. Several representative simulation methods are then proposed to tackle the governing functions of the electrohydrodynamics. Finally, prospects and challenges are raised, offering an insight into the new physics of the hybrid fluid under applied fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • An active bacterial anti-adhesion method was proposed. • The relationship between the influence factors and self-actuate motion is revealed. • A star-shaped intelligent response platform (SIRP) was constructed. • SIRP showed good active bacterial anti-adhesion and sterilization ability. The adhesion of adverse bacteria to material surfaces increases the risk of microbial corrosion and bacterial transmission. Superhydrophobic and superhydrophilic-type bacterial anti-adhesion approaches have been explored; however, these approaches are static and passive. This study proposes an active-bacterial anti-adhesion strategy based on the directional transportation of bacterial droplets on a star-shaped intelligent response platform (SIRP) for droplet self-actuation. Bacteria and other droplets can self-actuate on the SIRP, where droplets are in a superhydrophobic Cassie–Baxter wetting state, owing to the generated Laplace pressure gradient force on the wedge-shaped groove and extremely small adhesion resistance. The velocity and distance travelled of self-actuated droplets depend on various factors such as the opening angle, etching depth of the wedge-shaped groove, modified perfluorodecyltrimethoxysilane density, and droplet volume. Experimental and finite element simulation results confirm the continuous increase and sharp decrease in Laplace pressure difference in the self-actuated and non-self-actuated zones, respectively. The SIRP demonstrates superior bacterial anti-adhesion during bacterial droplet self-actuation and a very smart infrared-sensing sterilization or micro-reaction response to different types of droplets. The SIRP not only opens a new avenue for active bacterial anti-adhesion strategies but also offers a promising application for smart controllable micro-reactions. [ABSTRACT FROM AUTHOR]

Surface tension plays a core role in dominating various surface and interface phenomena. For liquid metals with high melting temperature, a profound understanding of the behaviors of surface tension is crucial in industrial processes such as casting, welding, and solidification, etc. Recently, the room temperature liquid metal (RTLM) mainly composed of gallium-based alloys has caused widespread concerns due to its increasingly realized unique virtues. The surface properties of such materials are rather vital in nearly all applications involved from chip cooling, thermal energy harvesting, hydrogen generation, shape changeable soft machines, printed electronics to 3D fabrication, etc. owing to its pretty large surface tension of approximately 700 mN/m. In order to promote the research of surface tension of RTLM, this paper is dedicated to present an overview on the roles and mechanisms of surface tension of liquid metal and summarize the latest progresses on the understanding of the basic knowledge, theories, influencing factors and experimental measurement methods clarified so far. As a practical technique to regulate the surface tension of RTLM, the fundamental principles and applications of electrowetting are also interpreted. Moreover, the unique phenomena of RTLM surface tension issues such as surface tension driven selfactuation, modified wettability on various substrates and the functions of oxides are discussed to give an insight into the acting mechanism of surface tension. Furthermore, future directions worthy of pursuing are pointed out. [ABSTRACT FROM AUTHOR]

Drug delivery, minimally-invasive surgery, and a hospital-in-the-body are highly desirable for meeting the rapidly growing needs of nanorobot. This paper reports a Z-shaped gold/platinum (Au/Pt) hybrid nanorobot which realizes the self-rotational movement without an external force field. The Z-shaped Au/Pt hybrid nanorobot was fabricated by focused ion beam (FIB) and plasma sputtering. The purity of the nanorobot was tested by energy dispersive X-ray analysis (EDS). The weight percentage of Pt and Au at the tip were 94.28% and 5.72%, respectively. The weight percentage of Pt and Au at the bottom were 17.39% and 82.75%, respectively. The size of the nanorobot was 2.58 x 10-16 m² and the mass of the nanorobot was 8.768 x 10-8 kg. The driving force of the nanorobot was 9.76 x 10-14 N at the 6.9% concentration of hydrogen peroxide solution. The rotation speed was 13 rpm, 14 rpm, and 19 rpm at 5.6%, 6.2%, and 7.8% concentrations, respectively. [ABSTRACT FROM AUTHOR]

This paper presents the first theoretical and experimental study on the power handling capabilities of electrostatically tunable MEMS cavity filters. The theoretical analysis indicates that the frequency-dependent RF voltage inside a narrowband filter may play an important role in the generation of electromechanical nonlinearities such as frequency response distortion, frequency shift, and bifurcation instability. This analysis also reveals that the filter's power handling capability is dependent on several critical factors, including the capacitive gap, stiffness of the diaphragm actuator, and the overall quality factor (Q) of the evanescent-mode (EVA) resonators. A nonlinear computer-aided design (CAD) model is proposed as a practical tool for capturing the important tradeoffs in high-power design. An EVA tunable resonator and a two-pole 2% filter are fabricated and measured as vehicles to validate the theory and the CAD model. Specifically, a medium-power filter with a tuning range of 2.35–3.21 GHz (1.37:1) and an extracted unloaded quality factor (Q_u) of 356–405 shows measured power levels of 23.4 dBm (0.22 W) before bifurcation instability occurs. The measured IIP3 of this filter are 52.1 dBm. The theory and modeling, backed up by the measurements, provide significant insights into the high-power design of electrostatic tunable cavity filters. [ABSTRACT FROM AUTHOR]

This paper discusses reliability issues in torsional MEMS varactor. Self-actuation due to high ac signals is analyzed, and solutions are proposed. The mode of failure at high actuation voltages is analyzed and established through experiments. Issues like stiction due to high voltages and effect of high residual stress are studied experimentally. [ABSTRACT FROM PUBLISHER]

The contradiction between human's strong demand of fossil fuels and their limited reserves becomes increasingly severe. Without external power input, intelligent materials responding sharply and reversibly to various external stimuli are the topic of intense research these years, especially the self-actuation and self-sensing materials. The promising family of these materials will play a significant role in energy-saving, low-cost and environment-friendly intelligent systems in the future. This review summarizes the latest advances in self-actuation and self-sensing materials. The synthetic strategies, morphologies and performance of these materials are introduced, as well as their applications in energy harvest, self-powering sensors, wearable devices, etc. Finally, tentative conclusions and assessments regarding the opportunities and challenges for the future development of these materials are presented. Image 1 • This review concerns recent progress and challenges in the development of self-actuation and self-sensing materials. • Explanation the mechanisms of stimuli responsiveness together with evaluation of the properties of these materials. • Perspectives of the applications of self-sensing materials in analytical techniques and portable sensing systems. [ABSTRACT FROM AUTHOR]