Human-object interaction, connectedness with nature, and life satisfaction: a cross-sectional study.

Introduction: This study aimed to elucidate the relationship between interactions with everyday objects (e.g., stationery, clothing, and tools) and one's connectedness with nature, environmentally conscious behavior, and life satisfaction. While previous research has predominantly explored the link between awareness of and behavior toward nature with direct education and experience related to the natural environment, we focused on the origins of the objects that surround us, which are inherently derived from nature. Methods: We conducted an online survey with 1,102 Japanese participants, who completed an object-interaction measure assessing the two dimensions of care and learning, and measures of connectedness with nature, pro-environmental behavior, and life satisfaction. Results: Interactions with everyday objects involving care and learning were significantly associated with a sense of connectedness with nature, pro-environmental behavior, and life satisfaction. Discussion: The study highlights that interactions with everyday artifacts are not isolated experiences but are related to broader awareness of and behavior toward the natural world, and with individual life satisfaction. Hence, environmental awareness and actions can extend beyond direct environmental experiences and encompass daily interactions with objects. Future research could examine how cultural factors shape the relationship between human-object interactions, connection with nature, environmentally conscious behavior, and life satisfaction.

Acoustohydrodynamic micromixers: Basic mixing principles, programmable mixing prospectives, and biomedical applications.

Acoustohydrodynamic micromixers offer excellent mixing efficiency, cost-effectiveness, and flexible controllability compared with conventional micromixers. There are two mechanisms in acoustic micromixers: indirect influence by induced streamlines, exemplified by sharp-edge micromixers, and direct influence by acoustic waves, represented by surface acoustic wave micromixers. The former utilizes sharp-edge structures, while the latter employs acoustic wave action to affect both the fluid and its particles. However, traditional micromixers with acoustic bubbles achieve significant mixing performance and numerous programmable mixing platforms provide excellent solutions with wide applicability. This review offers a comprehensive overview of various micromixers, elucidates their underlying principles, and explores their biomedical applications. In addition, advanced programmable micromixing with impressive versatility, convenience, and ability of cross-scale operations is introduced in detail. We believe this review will benefit the researchers in the biomedical field to know the micromixers and find a suitable micromixing method for their various applications.

Magnetic Microrobots Fabricated by Photopolymerization and Assembly.

Magnetic soft microrobots have great potential to access narrow spaces and conduct multiple tasks in the biomedical field. Until now, drug delivery, microsurgery, disease diagnosis, and dredging the blocked blood vessel have been realized by magnetic soft microrobots in vivo or in vitro. However, as the tasks become more and more complex, more functional units have been embedded in the body of the developed magnetic microrobots. These magnetic soft microrobots with complex designed geometries, mechanisms, and magnetic orientation are now greatly challenging the fabrication of the magnetic microrobots. In this paper, we propose a new method combining photopolymerization and assembly for the fabrication of magnetic soft microrobots. Utilizing the micro-hand assembly system, magnetic modules with different shapes and materials are firstly arrayed with precise position and orientation control. Then, the developed photopolymerization system is employed to fix and link these modules with soft materials. Based on the proposed fabrication method, 3 kinds of soft magnetic microrobots were fabricated, and the fundamental locomotion was presented. We believe that the presented fabrication strategy could help accelerate the clinical application of magnetic microrobots.

Field-Controlled Microrobots Fabricated by Photopolymerization.

Field-controlled microrobots have attracted extensive research in the biological and medical fields due to the prominent characteristics including high flexibility, small size, strong controllability, remote manipulation, and minimal damage to living organisms. However, the fabrication of these field-controlled microrobots with complex and high-precision 2- or 3-dimensional structures remains challenging. The photopolymerization technology is often chosen to fabricate field-controlled microrobots due to its fast-printing velocity, high accuracy, and high surface quality. This review categorizes the photopolymerization technologies utilized in the fabrication of field-controlled microrobots into stereolithography, digital light processing, and 2-photon polymerization. Furthermore, the photopolymerized microrobots actuated by different field forces and their functions are introduced. Finally, we conclude the future development and potential applications of photopolymerization for the fabrication of field-controlled microrobots.

Transmembrane capability of DNA origami sheet enhanced by 3D configurational changes.

DNA origami-engineered nanostructures are widely used in biomedical applications involving transmembrane delivery. Here, we propose a method to enhance the transmembrane capability of DNA origami sheets by changing their configuration from two-dimensional to three-dimensional. Three DNA nanostructures are designed and constructed, including the two-dimensional rectangular DNA origami sheet, the DNA tube, and the DNA tetrahedron. The latter two are the variants of the DNA origami sheet with three-dimensional morphologies achieved through one-step folding and multi-step parallel folding separately. The design feasibility and structural stability of three DNA nanostructures are confirmed by molecular dynamics simulations. The fluorescence signals of the brain tumor models demonstrate that the tubular and the tetrahedral configurational changes could dramatically increase the penetration efficiency of the original DNA origami sheet by about three and five times, respectively. Our findings provide constructive insights for further rational designs of DNA nanostructures for transmembrane delivery.

Cell pairing for biological analysis in microfluidic devices.

Cell pairing at the single-cell level usually allows a few cells to contact or seal in a single chamber and provides high-resolution imaging. It is pivotal for biological research, including understanding basic cell functions, creating cancer treatment technologies, developing drugs, and more. Laboratory chips based on microfluidics have been widely used to trap, immobilize, and analyze cells due to their high efficiency, high throughput, and good biocompatibility properties. Cell pairing technology in microfluidic devices provides spatiotemporal research on cellular interactions and a highly controlled approach for cell heterogeneity studies. In the last few decades, many researchers have emphasized cell pairing research based on microfluidics. They designed various microfluidic device structures for different biological applications. Herein, we describe the current physical methods of microfluidic devices to trap cell pairs. We emphatically summarize the practical applications of cell pairing in microfluidic devices, including cell fusion, cell immunity, gap junction intercellular communication, cell co-culture, and other applications. Finally, we review the advances and existing challenges of the presented devices and then discuss the possible development directions to promote medical and biological research.

Recent Progress of Magnetically Actuated DNA Micro/Nanorobots.

In the past few decades, the field of DNA origami-based micro/nanotechnology has developed dramatically and spawned attention increasingly, as its high integrality, rigid structure, and excellent resistance ability to enzyme digestion. Many two-dimensional and three-dimensional DNA nanostructures coordinated with optical, chemical, or magnetic triggers have been designed and assembled, extensively used as versatile templates for molecular robots, nanosensors, and intracellular drug delivery. The magnetic field has been widely regarded as an ideal driving and operating system for micro/nanomaterials, as it does not require high-intensity lasers like light control, nor does it need to change the chemical composition similar to chemical activation. Herein, we review the recent achievements in the induction and actuation of DNA origami-based nanodevices that respond to magnetic fields. These magnetic actuation-based DNA nanodevices were regularly combined with magnetic beads or gold nanoparticles and applied to generate single-stranded scaffolds, assemble various DNA nanostructures, and purify specific DNA nanostructures. Moreover, they also produced artificial magnetism or moved regularly driven by external magnetic fields to explain deeper scientific issues.

Magnetically Driven Soft Continuum Microrobot for Intravascular Operations in Microscale.

Remotely controlled soft continuum robots with active steering capability have broad prospects in medical applications. However, conventional continuum robots have the miniaturization challenge. This paper presents a microscale soft continuum microrobot with steering and locomotion capabilities based on magnetic field actuation. The magnetically driven soft continuum microrobot is made of NdFeB particles and polydimethylsiloxane (PDMS), and it can be as small as 200 µm in diameter. Moreover, a hydrogel layer is covered on the surface of the microrobot, which not only overcomes the adhesion force between the microobjects and the soft tip but also reduces the friction between the microrobot and substrate. The performance test indicates the soft continuum microrobot featured excellent control and steering capabilities. The experimental results demonstrate that the soft continuum microrobot can travel through the microfluidic channel by its own vibration and flexibly steer in a bifurcation environment. Moreover, the micromanipulation of microbeads in the microfluidic channels proves that the proposed microscale soft continuum microrobot has a great potential for intravascular manipulation.

Vision-Based Automated Control of Magnetic Microrobots.

Magnetic microrobots are vital tools for targeted therapy, drug delivery, and micromanipulation on cells in the biomedical field. In this paper, we report an automated control and path planning method of magnetic microrobots based on computer vision. Spherical microrobots can be driven in the rotating magnetic field generated by electromagnetic coils. Under microscopic visual navigation, robust target tracking is achieved using PID-based closed-loop control combined with the Kalman filter, and intelligent obstacle avoidance control can be achieved based on the dynamic window algorithm (DWA) implementation strategy. To improve the performance of magnetic microrobots in trajectory tracking and movement in complicated environments, the magnetic microrobot motion in the flow field at different velocities and different distribution obstacles was investigated. The experimental results showed that the vision-based controller had an excellent performance in a complex environment and that magnetic microrobots could be controlled to move to the target position smoothly and accurately. We envision that the proposed method is a promising opportunity for targeted drug delivery in biological research.

Time-Resolved Infrared Spectroscopy with Multivariate Analysis on Photoinduced Proton Transfer in Aromatic Urea-Acetate Anion Complexes.

1-Anthracen-2-yl-3-phenylurea (2PUA) is an aromatic urea compound, which forms a hydrogen-bonded complex with an acetate anion (AcO-), 2PUA-AcO- complex. We investigated the photoinduced reaction of the 2PUA-AcO- complex in dimethyl sulfoxide (DMSO) by nanosecond time-resolved infrared (TR-IR) spectroscopy. TR-IR spectra obtained after the photoexcitation of 2PUA with the equal concentration of AcO- were consistently explained by a photoinduced proton transfer model. The spectral and temporal profiles of the TR-IR spectra largely depended on concentration conditions of 2PUA and AcO-. Under the condition where excessive amounts of AcO- existed, the TR-IR spectra contained an unexpected signal whose amplitude was related to the concentration of free AcO- in the solution. Using singular value decomposition analysis of the concentration-dependent TR-IR spectra, we extracted the spectral component that reflects the photoinduced reaction of the 2PUA-AcO- complex. The extracted spectrum resembled the TR-IR spectrum obtained under the equal concentration condition, indicating that the same proton transfer occurs during the photoinduced reaction of the 2PUA-AcO- complex irrespective of the concentration conditions. Comparing the steady-state and transient IR spectra of the 2PUA with AcO- in DMSO with density functional theory calculations suggests that both 2PUA-AcO- complex and tautomer species interact with solvent DMSO molecules in their electronic ground states to a large extent.

A tetrahedral DNA nanorobot with conformational change in response to molecular trigger.

Dynamic DNA origami nanostructures that respond to external stimuli are promising platforms for cargo delivery and nanoscale sensing. However, the low stability of such nanostructures under physiological conditions presents a major obstacle for their use in biomedical applications. This article describes a stable tetrahedral DNA nanorobot (TDN) programmed to undergo a controlled conformational change in response to epithelial cell adhesion molecule (EpCAM), a molecular biomarker specifically expressed on the circulating tumor cells. Multiresolution molecular dynamics simulations verified the overall stability of the folded TDN design and characterized local distortions in the folded structure. Atomic force microscopy and gel electrophoresis results showed that tetragonal structures are more stable than unfolded DNA origami sheets. Live cell experiments demonstrated the low cytotoxicity and target specificity of TDN. In summary, the proposed TDN can not only effectively resist nuclease catalysis but also has the potential to monitor EpCAM-positive cells precisely.

Bio-assembling and Bioprinting for Engineering Microvessels from the Bottom Up.

Blood vessels are essential in transporting nutrients, oxygen, metabolic wastes, and maintaining the homeostasis of the whole human body. Mass of engineered microvessels is required to deliver nutrients to the cells included in the constructed large three-dimensional (3D) functional tissues by diffusion. It is a formidable challenge to regenerate microvessels and build a microvascular network, mimicking the cellular viabilities and activities in the engineered organs with traditional or existing manufacturing techniques. Modular tissue engineering adopting the "bottom-up" approach builds one-dimensional (1D) or two-dimensional (2D) modular tissues in micro scale first and then uses these modules as building blocks to generate large tissues and organs with complex but indispensable microstructural features. Building the microvascular network utilizing this approach could be appropriate and adequate. In this review, we introduced existing methods using the "bottom-up" concept developed to fabricate microvessels including bio-assembling powered by different micromanipulation techniques and bioprinting utilizing varied solidification mechanisms. We compared and discussed the features of the artificial microvessels engineered by these two strategies from multiple aspects. Regarding the future development of engineering the microvessels from the bottom up, potential directions were also concluded.

Automated Cell Mechanical Characterization by On-Chip Sequential Squeezing: From Static to Dynamic.

The mechanical properties of cells are harmless biomarkers for cell identification and disease diagnosis. Although many systems have been developed to evaluate the static mechanical properties of cells for biomedical research, their robustness, effectiveness, and cost do not meet clinical requirements or the experiments with a large number of cell samples. In this paper, we propose an approach for on-chip cell mechanical characterization by analyzing the dynamic behavior of cells as they pass through multiple constrictions. The proposed serpentine microfluidic channel consisted of 20 constrictions connected in series and divided into five rows for tracking cell dynamic behavior. Assisted by computer vision, the squeezing time of each cell through five rows of constrictions was automatically collected and filtered to evaluate the cell's mechanical deformability. We observed a decreasing passage time and increasing dynamic deformability of the cells as they passed through the multiple constrictions. The deformability increase rate of the HeLa cells was eight times greater than that of MEF cells. Moreover, the weak correlation between the deformability increase rate and the cell size indicated that cell recognition based on measuring the deformability increase rate could hardly be affected by the cell size variation. These findings showed that the deformability increase rate of the cell under on-chip sequential squeezing as a new index has great potential in cancer cell recognition.

Endoluminal Motion Recognition of a Magnetically-Guided Capsule Endoscope Based on Capsule-Tissue Interaction Force.

A magnetically-guided capsule endoscope, embedding flexible force sensors, is designed to measure the capsule-tissue interaction force. The flexible force sensor is composed of eight force-sensitive elements surrounding the internal permanent magnet (IPM). The control of interaction force acting on the intestinal wall can reduce patient's discomfort and maintain the magnetic coupling between the external permanent magnet (EPM) and the IPM during capsule navigation. A flexible force sensor can achieve this control. In particular, by analyzing the signals of the force sensitive elements, we propose a method to recognize the status of the motion of the magnetic capsule, and provide corresponding formulas to evaluate whether the magnetic capsule follows the motion of the external driving magnet. Accuracy of the motion recognition in Ex Vivo tests reached 94% when the EPM was translated along the longitudinal axis. In addition, a method is proposed to realign the EPM and the IPM before the loss of their magnetic coupling. Its translational error, rotational error, and runtime are 7.04 ± 0.71 mm, 3.13 ± 0.47∘, and 11.4 ± 0.39 s, respectively. Finally, a control strategy is proposed to prevent the magnetic capsule endoscope from losing control during the magnetically-guided capsule colonoscopy.

Magnetic Driven Two-Finger Micro-Hand with Soft Magnetic End-Effector for Force-Controlled Stable Manipulation in Microscale.

In recent years, micromanipulators have provided the ability to interact with micro-objects in industrial and biomedical fields. However, traditional manipulators still encounter challenges in gaining the force feedback at the micro-scale. In this paper, we present a micronewton force-controlled two-finger microhand with a soft magnetic end-effector for stable grasping. In this system, a homemade electromagnet was used as the driving device to execute micro-objects manipulation. There were two soft end-effectors with diameters of 300 µm. One was a fixed end-effector that was only made of hydrogel, and the other one was a magnetic end-effector that contained a uniform mixture of polydimethylsiloxane (PDMS) and paramagnetic particles. The magnetic force on the soft magnetic end-effector was calibrated using an atomic force microscopy (AFM) probe. The performance tests demonstrated that the magnetically driven soft microhand had a grasping range of 0-260 µm, which allowed a clamping force with a resolution of 0.48 µN. The stable grasping capability of the magnetically driven soft microhand was validated by grasping different sized microbeads, transport under different velocities, and assembly of microbeads. The proposed system enables force-controlled manipulation, and we believe it has great potential in biological and industrial micromanipulation.

Opposite substituent effects in the ground and excited states on the acidity of N-H fragments involved in proton transfer reaction in aromatic urea compounds.

To investigate substitution effects on excited-state intermolecular proton transfer (ESPT) reactions as well as acidity of proton donating fragments in the ground state, we synthesized substituted anthracen-2-yl-3-phenylurea derivatives that form a hydrogen bonds with acetate anions and undergo ESPT reaction. Fluorescence lifetime measurements and their kinetic analyses revealed that the trifluoromethyl group on the phenyl ring as an electron-withdrawing group caused a slow ESPT reaction despite an increase in the acidity of the N-H fragment in the ground state. In contrast, the methoxy group as a donating group leads to a fast ESPT reaction despite a reduction of the acidity of the N-H fragment in the ground state. These effects of substituents on ESPT reaction are due to their influence on the charge transfer reaction, which occurs from the N-H fragment to the anthryl ring to increase the acidity of N-H followed by ESPT reaction, over the urea unit by a combination of resonance and inductive effects. These opposing effects of substituents on the acidity of the urea unit in the ground and excited states provide an important insight in balancing the reactivity of proton transfer reaction in both the excited and ground states.

A Wearable Navigation Device for Visually Impaired People Based on the Real-Time Semantic Visual SLAM System.

Wearable auxiliary devices for visually impaired people are highly attractive research topics. Although many proposed wearable navigation devices can assist visually impaired people in obstacle avoidance and navigation, these devices cannot feedback detailed information about the obstacles or help the visually impaired understand the environment. In this paper, we proposed a wearable navigation device for the visually impaired by integrating the semantic visual SLAM (Simultaneous Localization And Mapping) and the newly launched powerful mobile computing platform. This system uses an Image-Depth (RGB-D) camera based on structured light as the sensor, as the control center. We also focused on the technology that combines SLAM technology with the extraction of semantic information from the environment. It ensures that the computing platform understands the surrounding environment in real-time and can feed it back to the visually impaired in the form of voice broadcast. Finally, we tested the performance of the proposed semantic visual SLAM system on this device. The results indicate that the system can run in real-time on a wearable navigation device with sufficient accuracy.

Bubbles in microfluidics: an all-purpose tool for micromanipulation.

In recent decades, the integration of microfluidic devices and multiple actuation technologies at the microscale has greatly contributed to the progress of related fields. In particular, microbubbles are playing an increasingly important role in microfluidics because of their unique characteristics that lead to specific responses to different energy sources and gas-liquid interactions. Many effective and functional bubble-based micromanipulation strategies have been developed and improved, enabling various non-invasive, selective, and precise operations at the microscale. This review begins with a brief introduction of the morphological characteristics and formation of microbubbles. The theoretical foundations and working mechanisms of typical micromanipulations based on acoustic, thermodynamic, and chemical microbubbles in fluids are described. We critically review the extensive applications and the frontline advances of bubbles in microfluidics, including microflow patterns, position and orientation control, biomedical applications, and development of bubble-based microrobots. We lastly present an outlook to provide directions for the design and application of microbubble-based micromanipulation tools and attract the attention of relevant researchers to the enormous potential of microbubbles in microfluidics.

Development of a QUS Device to Evaluate Deterioration of Cortical Bone: Verification by HR-pQCT and Measurements in Healthy Individuals and Dialysis Patients.

INTRODUCTION: The objectives of this study were to identify what is reflected in cortical speed of sound (cSOS) measured by a cortical quantitative ultrasound (cortical QUS) device we have developed, and to investigate cSOS measurements in healthy individuals and dialysis patients. METHODS: The cSOS and the SOS were measured by cortical QUS and conventional QUS in 20 volunteers, and the correlations between these measurements and areal bone mineral density measured by dual-energy X-ray absorptiometry and bone microstructural parameters on high-resolution peripheral quantitative computed tomography were analyzed. The cSOS and the SOS were measured in 91 young adults (47 men, 44 women), 64 elderly people (30 men, 33 women), and 64 dialysis patients (33 men, 31 women). The period of hemodialysis and intact parathyroid hormoneevels were also investigated in the dialysis patients. RESULTS: cSOS was correlated with cortical tissue mineral density (tibia: r = 0.74, radius: r = 0.72) on high-resolution peripheral quantitative computed tomography, reflecting the degree of minaralization and microporosity of cortical bone. There was no correlation with the thickness of cortical bone, suggesting that it measured the bone quality rather than bone mass. Elderly women had lower cSOS than young adults (3865 ± 74 vs 3971 ± 63 m/s, p < 0.01). Many of dialysis patients showed very low cSOS and it was related to higher intact parathyroid hormone levels (male: ß = -0.67, female: ß = -0.60). CONCLUSIONS: Our cortical QUS device is capable of evaluating the qualitative degradation of cortical bone, which cannot be assessed by conventional QUS, and its use in combination with conventional QUS may provide a better understanding of fracture risk.

Citrus Naringenin Increases Neuron Survival in Optic Nerve Crush Injury Model by Inhibiting JNK-JUN Pathway.

Traumatic nerve injury activates cell stress pathways, resulting in neuronal death and loss of vital neural functions. To date, there are no available neuroprotectants for the treatment of traumatic neural injuries. Here, we studied three important flavanones of citrus components, in vitro and in vivo, to reveal their roles in inhibiting the JNK (c-Jun N-terminal kinase)-JUN pathway and their neuroprotective effects in the optic nerve crush injury model, a kind of traumatic nerve injury in the central nervous system. Results showed that both neural injury in vivo and cell stress in vitro activated the JNK-JUN pathway and increased JUN phosphorylation. We also demonstrated that naringenin treatment completely inhibited stress-induced JUN phosphorylation in cultured cells, whereas nobiletin and hesperidin only partially inhibited JUN phosphorylation. Neuroprotection studies in optic nerve crush injury mouse models revealed that naringenin treatment increased the survival of retinal ganglion cells after traumatic optic nerve injury, while the other two components had no neuroprotective effect. The neuroprotection effect of naringenin was due to the inhibition of JUN phosphorylation in crush-injured retinal ganglion cells. Therefore, the citrus component naringenin provides neuroprotection through the inhibition of the JNK-JUN pathway by inhibiting JUN phosphorylation, indicating the potential application of citrus chemical components in the clinical therapy of traumatic optic nerve injuries.