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Today, smart materials are commonly used in various fields of science and technology, such as medicine, electronics, soft robotics, the chemical industry, the automotive field, and many others. Smart polymeric materials hold good promise for the future due to their endless possibilities. This group of advanced materials can be sensitive to changes or the presence of various chemical, physical, and biological stimuli, e.g., light, temperature, pH, magnetic/electric field, pressure, microorganisms, bacteria, viruses, toxic substances, and many others. This review concerns the newest achievements in the area of smart polymeric materials. The recent advances in the designing of stimuli-responsive polymers are described in this paper. [ABSTRACT FROM AUTHOR]

Organic room temperature afterglow (ORTA) can be categorized into two key mechanisms: continuous thermally activated delayed fluorescence (TADF) and room-temperature phosphorescence (RTP), both of which involve a triplet excited state. However, triplet excited states are easily quenched by non-radiative transitions due to oxygen and molecular vibrations. Solid-phase systems provide a conducive environment for triplet excitons due to constrained molecular motion and limited oxygen permeation within closely packed molecules. The stimulated triplet state tends to release energy through radiative transitions. Despite numerous reports on RTP in solid-phase systems in recent years, the complexity of these systems precludes the formulation of a universal theory to elucidate the underlying principles. Several strategies for achieving ORTA luminescence in the solid phase have been developed, encompassing crystallization, polymer host-guest doping, and small molecule host-guest doping. Many of these systems exhibit luminescent responses to various physical stimuli, including light stimulation, mechanical stimuli, and solvent vapor exposure. The appearance of these intriguing luminescent phenomena in solid-phase systems underscores their significant potential applications in areas such as light sensing, biological imaging, and information security. [ABSTRACT FROM AUTHOR]

The electrical microenvironment is considered a pivotal determinant in various pathophysiological processes, including tissue homeostasis and wound healing. Consequently, extensive research endeavors have been directed toward applying electricity to cells and tissues through external force devices or biomaterial-based platforms. In addition to in situ electroconductive matrices, a new class of electroactive biomaterials responsive to stimuli has emerged as a focal point of interest. These electroactive materials, in response to intrinsic biochemical (e.g., glucose) or external physical stimuli (e.g., light, magnetism, stress), hold significant potential for cell stimulation and tissue regeneration. In this communication, we underscore this distinct category of electroactive biomaterials, discussing the currently developed biomaterial platforms and their biological roles in stimulating cells and tissues during the healing and regeneration process. We also critically evaluate the inherent limitations and challenges of these biomaterials while offering forward-looking insights into their promise for future clinical translations. [ABSTRACT FROM AUTHOR]

To adapt to the changes in nature, living systems adjust their structure and function according to the environmental conditions. Scientists are inspired by nature and try to create materials that can change their behavior depending on the situation, just like living organisms do to survive. The idea of intelligent materials comes from natural biological systems, which follow a mechanism of sensing, reacting, and learning. Smart polymers, also known as stimuli-responsive, are a group of materials that possess the ability to respond to specific stimuli by undergoing reversible changes in their properties. Smart polymers have amazing features that come from their flexibility and responsiveness. They can change their molecular structure and function to suit different external stimuli or environmental changes. These materials are like living systems that adapt to their surroundings. Smart polymers have unique and highly desirable properties that make them attractive for a wide range of applications in medicine. This article reviews provides a comprehensive review of the recent advances in smart functional polymers, exploring their responses to various stimuli, be it physical, chemical, or biological. It also discusses some of the most advanced medical applications of these polymers, showcasing their transformative potential as materials that dynamically adjust to their environment.

The use of lanthanide‐based metallogels presents a promising approach for the engineering of stimuli‐responsive gel materials. Stimuli‐responsive luminescent materials based on lanthanides have promising applications in bio‐applications and optical encoding. Synthetic supramolecular metallogels typically become kinetically trapped and usually do not exhibit time‐variable changes in their material properties. However, such supramolecular metallogels can switch between gel to sol when subjected to different external physical and chemical stimuli. This is because weak noncovalent interactions hold together the gel structure and are also influenced by the coordination dynamics of the metal‐ligand bond. This review summarizes recent research progress on stimuli‐responsive supramolecular lanthanide‐based luminescent metallogels. Chemical, physical, and multiple stimuli‐responsiveness of the metallogels are discussed elaborately based on the external stimulus sources. Finally, the latest challenges and opportunities for developing novel metallogels that respond to stimuli are discussed. [ABSTRACT FROM AUTHOR]

Polymeric biomaterials exhibit excellent physicochemical characteristics as a scaffold for cell and tissue engineering applications. Chemical modification of the polymers has been the primary mode of functionalization to enhance biocompatibility and regulate cellular behaviors such as cell adhesion, proliferation, differentiation, and maturation. Due to the complexity of the in vivo cellular microenvironments, however, chemical functionalization alone is usually insufficient to develop functionally mature cells/tissues. Therefore, the multifunctional polymeric scaffolds that enable electrical, mechanical, and/or magnetic stimulation to the cells, have gained research interest in the past decade. Such multifunctional scaffolds are often combined with exogenous stimuli to further enhance the tissue and cell behaviors by dynamically controlling the microenvironments of the cells. Significantly improved cell proliferation and differentiation, as well as tissue functionalities, are frequently observed by applying extrinsic physical stimuli on functional polymeric scaffold systems. In this regard, the present paper discusses the current state-of-the-art functionalized polymeric scaffolds, with an emphasis on electrospun fibers, that modulate the physical cell niche to direct cellular behaviors and subsequent functional tissue development. We will also highlight the incorporation of the extrinsic stimuli to augment or activate the functionalized polymeric scaffold system to dynamically stimulate the cells.

Abstract Background Cells in the human body experience different growth environments and conditions, such as compressive pressure and oxygen concentrations, depending on the type and location of the tissue. Thus, a culture device that emulates the environment inside the body is required to study cells outside the body. Methods A blanket-type cell culture device (Direct Contact Pressing: DCP) was fabricated with an alginate-based hydrogel. Changes in cell morphology due to DCP pressure were observed using a phase contrast microscope. The changes in the oxygen permeability and pressure according to the hydrogel concentration of DCP were analyzed. To compare the effects of DCP with normal or artificial hypoxic cultures, cells were divided based on the culture technique: normal culture, DCP culture device, and artificial hypoxic environment. Changes in phenotype, genes, and glycosaminoglycan amounts according to each environment were evaluated. Based on this, the mechanism of each culture environment on the intrinsic properties of conserving chondrocytes was suggested. Results Chondrocytes live under pressure from the surrounding collagen tissue and experience a hypoxic environment because collagen inhibits oxygen permeability. By culturing the chondrocytes in a DCP environment, the capability of DCP to produce a low-oxygen and physical pressure environment was verified. When human primary chondrocytes, which require pressure and a low-oxygen environment during culture to maintain their innate properties, were cultured using the hydrogel blanket, the original shapes and properties of the chondrocytes were maintained. The intrinsic properties could be recovered even in aged cells that had lost their original cell properties. Conclusions A DCP culture method using a biomimetic hydrogel blanket provides cells with an adjustable physical pressure and a low-oxygen environment. Through this technique, we could maintain the original cellular phenotypes and intrinsic properties of human primary chondrocytes. The results of this study can be applied to other cells that require special pressure and oxygen concentration control to maintain their intrinsic properties. Additionally, this technique has the potential to be applied to the re-differentiation of cells that have lost their original properties.

Emulsion as a fine dispersion of immiscible liquids has involved widespread applications in industry, pharmaceuticals, agriculture, and personal care. Stimuli‐responsive emulsions capable of on‐demand demulsification or changing their properties are required in many cases such as controllable release cargo, oil recovery, emulsifier recycling, and product separation, great progress is achieved in these areas. Among these various triggers, much effort is made to develop physical stimuli, due to the noninvasive and environmentally friendly characteristics. Physical stimuli‐responsive emulsions provide plenty of valuable practical applications in the fields of sustainable industry, biomedical reaction, drug delivery. Here, the recent development in the field of emulsions in response to physical stimuli consisting of temperature, light, magnetic fields, electrical fields, etc., is summarized. The preparation methods and mechanisms of physical stimuli‐responsive emulsions and their applications of catalysis reaction, drug delivery, and oil recovery are highlighted in this review. The future directions and outstanding problems of the physical stimuli‐responsive emulsions are also discussed. [ABSTRACT FROM AUTHOR]

Infections are regarded as the most severe complication associated with human health, which are urgent to be solved. Stimuli‐responsive materials are appealing therapeutic platforms for antibacterial treatments, which provide great potential for accurate theranostics. In this review, the advantages, the response mechanisms, and the key design principles of stimuli‐responsive antibacterial materials are highlighted. The biomedical applications, the current challenges, and future directions of stimuli‐responsive antibacterial materials are also discussed. First, the categories of stimuli‐responsive antibacterial materials are comprehensively itemized based on different sources of stimuli, including external physical environmental stimuli (e.g., temperature, light, electricity, salt, etc.) and bacterial metabolites stimuli (e.g., acid, enzyme, redox, etc.). Second, structural characteristics, design principles, and biomedical applications of the responsive materials are discussed, and the underlying interrelationships are revealed. The molecular structures and design principles are closely related to the sources of stimuli. Finally, the challenging issues of stimuli‐responsive materials are proposed. This review will provide scientific guidance to promote the clinical applications of stimuli‐responsive antibacterial materials. [ABSTRACT FROM AUTHOR]

Cell-free protein synthesis has been developed as a critical platform in synthetic biology. Unlike the cell-based synthesis system, cell-free system activates transcriptional and translational mechanisms in vitro, and can control protein synthesis by artificially adding components or chemicals. However, the control method puts forward higher requirements in terms of accurate and non-toxic control, which cannot be achieved by chemical substances. For cell-free system, physical signal is a kind of ideal spatiotemporal control approach to replace chemical substances, realizing high accuracy with little side effect. Here we review the methods of using physical signals to control gene expression in cell-free systems, including studies based on light, temperature, electric field, and magnetic force. The transfer of these switches into cell-free system further expands the flexibility and controllability of the system, thus further expanding the application capability of cell-free systems. Finally, existing problems such as signal source and signal transmission are discussed, and future applications in pharmaceutical production, delivery and industrial production are further looked into.

Macrophages play an essential role in immunotherapy and tissue regeneration owing to their remarkable plasticity and diverse functions. Recent bioengineering developments have focused on using external physical stimuli such as electric and magnetic fields, temperature, and compressive stress, among others, on micro/nanostructures to induce macrophage polarization, thereby increasing their therapeutic potential. However, it is difficult to find a concise review of the interaction between physical stimuli, advanced micro/nanostructures, and macrophage polarization. This review examines the present research on physical stimuli-induced macrophage polarization on micro/nanoplatforms, emphasizing the synergistic role of fabricated structure and stimulation for advanced immunotherapy and tissue regeneration. A concise overview of the research advancements investigating the impact of physical stimuli, including electric fields, magnetic fields, compressive forces, fluid shear stress, photothermal stimuli, and multiple stimulations on the polarization of macrophages within complex engineered structures, is provided. The prospective implications of these strategies in regenerative medicine and immunotherapeutic approaches are highlighted. This review will aid in creating stimuli-responsive platforms for immunomodulation and tissue regeneration., (© 2024 The Authors. Advanced Healthcare Materials published by Wiley‐VCH GmbH.)

Abstract Ferroelectric materials (FEMs), possessing piezoelectric, pyroelectric, inverse piezoelectric, nonlinear optic, ferroelectric‐photovoltaic, and many other properties, are attracting increasing attention in the field of biomedicine in recent years. Because of their versatile ability of interacting with force, heat, electricity, and light to generate electrical, mechanical, and optical signals, FEMs are demonstrating their unique advantages for biosensing, acoustics tweezer, bioimaging, therapeutics, tissue engineering, as well as stimulating biological functions. This review summarizes the current‐available FEMs and their state‐of‐the‐art fabrication techniques, as well as provides an overview of FEMs‐based applications in the field of biomedicine. Challenges and prospects for future development of FEMs for biomedical applications are also outlined.

Chih-Sheng Chiang,1 Jian-Yi Chen,1 Min-Yu Chiang,1 Kai-Ting Hou,1 Wei-Ming Li,1 Shwu-Jen Chang,2 San-Yuan Chen11Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan; 2Department of Biomedical Engineering, I-Shou University, Kaohsiung, TaiwanIntroduction: Stimulating the proliferation and differentiation of chondrocytes for the regeneration of articular cartilage is a promising strategy, but it is currently ineffective. Although both physical stimulation and growth factors play important roles in cartilage repair, their interplay remains unclear and requires further investigation. In this study, we aimed to clarify their contribution using a magnetic drug carrier that not only can deliver growth factors but also provide an external stimulation to cells in the two-dimensional environment.Materials and methods: We developed a nanocapsule (transforming growth factor-β1 [TGF-β1]-loaded magnetic amphiphilic gelatin nanocapsules [MAGNCs]; TGF-β1@MAGNCs) composed of hexanoic-anhydride-grafted gelatin and iron oxide nanoparticles to provide a combination treatment of TGF-β1 and magnetically induced physical stimuli. With the expression of Arg-Gly-Asp peptide in the gelatin, the TGF-β1@MAGNCs have an inherent affinity for chondrogenic ATDC5 cells.Results: In the absence of TGF-β1, ATDC5 cells treated with a magnetic field show significantly upregulated Col2a1 expression. Moreover, TGF-β1 slowly released from biodegradable TGF-β1@MAGNCs further improves the differentiation with increased expression of Col2a1 and Aggrecan.Conclusion: Our study shows the time-dependent interplay of physical stimuli and growth factors on chondrogenic regeneration, and demonstrates the promising use of TGF-β1@MAGNCs for articular cartilage repair.Keywords: physical stimuli, chondrogenic regeneration, TGF-β1, amphiphilic gelatin, combination stimuli

Ferroelectric materials (FEMs), possessing piezoelectric, pyroelectric, inverse piezoelectric, nonlinear optic, ferroelectric‐photovoltaic, and many other properties, are attracting increasing attention in the field of biomedicine in recent years. Because of their versatile ability of interacting with force, heat, electricity, and light to generate electrical, mechanical, and optical signals, FEMs are demonstrating their unique advantages for biosensing, acoustics tweezer, bioimaging, therapeutics, tissue engineering, as well as stimulating biological functions. This review summarizes the current‐available FEMs and their state‐of‐the‐art fabrication techniques, as well as provides an overview of FEMs‐based applications in the field of biomedicine. Challenges and prospects for future development of FEMs for biomedical applications are also outlined. [ABSTRACT FROM AUTHOR]

Nanocomposite polymers have received considerable interest in research for the last three decades. Those nanocomposite polymers that are sensitive to a stimulus such as pH, temperature, magnetism, and electricity, among others, called smart or intelligent nanocomposite polymers had received even greater attention due to their potential technological applications. Applications of these polymers include flexible electronic devices, sensors, self-healing polymers, shape-memory materials, etc. The sensitivity of the material can come from both the polymer that acts as a matrix and the nanofiller, resulting in a material that combines properties of each of its components and that each one will not have separately. This mini-review aims to provide an update on the most recent and significant applications in the area of stimuli-responsive polymer nanocomposites, emphasizing the most innovative applications in biomedicine and catalysis developed in the last three years. [ABSTRACT FROM AUTHOR]

Tissue engineering (TE) is a strongly expanding research area. TE approaches require biocompatible scaffolds, cells, and different applied stimuli, which altogether mimic the natural tissue microenvironment. Also, the extracellular matrix serves as a structural base for cells and as a source of growth factors and biophysical cues. The 3D characteristics of the microenvironment is one of the most recognized key factors for obtaining specific cell responses in vivo, being the physical cues increasingly investigated. Supporting those advances is the progress of smart and multifunctional materials design, whose properties improve the cell behavior control through the possibility of providing specific chemical and physical stimuli to the cellular environment. In this sense, a varying set of bioreactors that properly stimulate those materials and cells in vitro, creating an appropriate biomimetic microenvironment, is developed to obtain active bioreactors. This review provides a comprehensive overview on the important microenvironments of different cells and tissues, the smart materials type used for providing such microenvironments and the specific bioreactor technologies that allow subjecting the cells/tissues to the required biomimetic biochemical and biophysical cues. Further, it is shown that microfluidic bioreactors represent a growing and interesting field that hold great promise for achieving suitable TE strategies. [ABSTRACT FROM AUTHOR]

Bacterial environmental colonization and subsequent biofilm formation on surfaces represents a significant and alarming problem in various fields, ranging from contamination of medical devices up to safe food packaging. Therefore, the development of surfaces resistant to bacterial colonization is a challenging and actively solved task. In this field, the current promising direction is the design and creation of nanostructured smart surfaces with on-demand activated amicrobial protection. Various surface activation methods have been described recently. In this review article, we focused on the “physical” activation of nanostructured surfaces. In the first part of the review, we briefly describe the basic principles and common approaches of external stimulus application and surface activation, including the temperature-, light-, electric- or magnetic-field-based surface triggering, as well as mechanically induced surface antimicrobial protection. In the latter part, the recent achievements in the field of smart antimicrobial surfaces with physical activation are discussed, with special attention on multiresponsive or multifunctional physically activated coatings. In particular, we mainly discussed the multistimuli surface triggering, which ensures a better degree of surface properties control, as well as simultaneous utilization of several strategies for surface protection, based on a principally different mechanism of antimicrobial action. We also mentioned several recent trends, including the development of the to-detect and to-kill hybrid approach, which ensures the surface activation in a right place at a right time.

Despite being very simple organisms, bacteria possess an outstanding ability to adapt to different environments. Their long evolutionary history, being exposed to vastly different physicochemical surroundings, allowed them to detect and respond to a wide range of signals including biochemical, mechanical, electrical, and magnetic ones. Taking into consideration their adapting mechanisms, it is expected that novel materials able to provide bacteria with specific stimuli in a biomimetic context may tailor their behavior and make them suitable for specific applications in terms of anti-microbial and pro-microbial approaches. This review maintains that electroactive smart materials will be a future approach to be explored in microbiology to obtain novel strategies for fighting the emergence of live threatening antibiotic resistance.

Adult stem cells are undifferentiated elements able to self-renew or differentiate to maintain tissue integrity. Within this context, stem cells are able to divide in a symmetric fashion, feature characterising all the somatic cells, or in an asymmetric way, which leads daughter cells to different fates. It is worth highlighting that cell polarity have a critical role in regulating stem cell asymmetric division and the proper control of cell division depends on different proteins involved in cell development, differentiation and maintenance of tissue homeostasis. Moreover, the interaction between cells and the extracellular matrix are crucial in influencing cell behavior, included in terms of mechanical properties as cytoskeleton plasticity and remodelling, and membrane tension. Finally, the activation of specific transcriptional program and epigenetic modifications contributes to cell fate determination, through modulation of cellular signalling cascades. It is well known that physical and mechanical stimuli are able to influence biological systems, and in this context, the effects of electromagnetic fields (EMFs) have already shown a considerable role, even though there is a lack of knowledge and much remains to be done around this topic. In this review, we summarize the historical background of EMFs applications and the main molecular mechanism involved in cellular remodelling, with particular attention to cytoskeleton elasticity and cell polarity, required for driving stem cell behavior. [ABSTRACT FROM AUTHOR]

In a series of studies using physical targets, we examined the effect of lateral retinal motion on stereoscopic depth discrimination thresholds. We briefly presented thin vertical lines, along with a fixation marker, at speeds ranging from 0 to 16 deg·s-1. Previous investigations of the effect of retinal motion on stereoacuity consistently show that there is little impact of retinal motion up to 2 deg·s-1, however, thresholds appear to rise steeply at higher velocities (greater than 3 deg·s-1). These prior experiments used computerized displays to generate their stimuli. In contrast, with our physical targets we find that stereoacuity is stable up to 16 deg·s-1, even in the presence of appreciable smearing due to visual persistence. We show that this discrepancy cannot be explained by differences in viewing time, prevalence of motion smear or by high frequency flicker due to display updates. We conclude that under natural viewing conditions observers are able to make depth discrimination judgements using binocular disparity signals that are rapidly acquired at stimulus onset. [ABSTRACT FROM AUTHOR]

Abstract The design of a delivery system allowing targeted and controlled drug release has been considered one of the main strategies used to provide individualized cancer therapy, to improve survival statistics, and to enhance quality-of-life. External stimuli including low- and high-penetration light have been shown to have the ability to turn drug delivery on and off in a non-invasive remotely-controlled fashion. The success of this approach has been closely related to the development of a variety of drug delivery systems – from photosensitive liposomes to gold nanocages – and relies on multiple mechanisms of drug release activation. In this review, we make reference to the two extremes of the light spectrum and their potential as triggers for the delivery of antitumor drugs, along with the most recent achievements in preclinical trials and the challenges to an efficient translation of this technology to the clinical setting. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

A current approach to obtain bioengineered lungs as a future alternative for transplantation is based on seeding stem cells on decellularized lung scaffolds. A fundamental question to be solved in this approach is how to drive stem cell differentiation onto the different lung cell phenotypes. Whereas the use of soluble factors as agents to modulate the fate of stem cells was established from an early stage of the research with this type of cells, it took longer to recognize that the physical microenvironment locally sensed by stem cells (e.g. substrate stiffness, 3D architecture, cyclic stretch, shear stress, air-liquid interface, oxygenation gradient) also contributes to their differentiation. The potential role played by physical stimuli would be particularly relevant in lung bioengineering since cells within the organ are physiologically subjected to two main stimuli required to facilitate efficient gas exchange: air ventilation and blood perfusion across the organ. The present review focuses on describing how the cell mechanical microenvironment can modulate stem cell differentiation and how these stimuli could be incorporated into lung bioreactors for optimizing organ bioengineering. [ABSTRACT FROM AUTHOR]

Tissue engineering strategies rely on suitable membranes and scaffolds, providing the necessary physicochemical stimuli to specific cells. This review summarizes the main results on piezoelectric polymers, in particular poly(vinylidene fluoride), for muscle and bone cell culture. Further, the relevance of polymer microstructure and surface charge on cell response is demonstrated. Together with the necessary biochemical cues, the proper design of piezoelectric polymers can open the way to novel and more reliable tissue engineering strategies for cells in which electromechanical stimuli are present in their environment. [ABSTRACT FROM AUTHOR]

Spine diseases are a worldwide social problem affecting increasingly high numbers of and younger individuals. The main complaints of patients with lumbar discopathy are pain sensations. The incidence of lumbar spine pain is increasingly high; therefore, lumbar pain disorders are called civilization diseases of our century. Effective treatment methods for lumbar pain that could be an alternative to pharmacological therapy are essential, particularly for patients with chronic pain. The aim of the study was to assess the effectiveness of physiotherapeutic interventions for the treatment of lumbar discopathy. In the years 2008-2009, physical methods were used in 70 patients with lumbar pain. They were supported by pharmacotherapy, massage and kinesitherapy in 38 patients. Six individuals were treated with pharmacotherapy alone. The present study focused on patients treated with physiotherapeutic interventions for lumbar discopathy. The study encompassed 70 patients subjected to the 21- day sanatorium rehabilitation. The age of patients ranged from 43 to 75 years (mean age - 59 years). Patients were divided into three age groups: Group I aged 43-55 years, 35 male patients (35%), Group II aged 56-65 years, 20 male patients (20%), Group III aged 66-75 years, 15 female patients (15%). Medical histories and physical examinations of patients were considered. The medical history data regarded the age of patients, time of the first pain sensations experienced and type of work. Physical examinations included:1. the Laitinen pain questionnaire, 2. the presence of Lasegue's sign, 3, evaluation of the range of lumbar mobility. The following statistical methods were used to analyse measurement results: an arithmetic mean (...); standard deviation (SD); minimum-maximum values (E...); a change in ... Δ... (%). The Student's t test for dependent groups was applied to evaluate the differences in parameters before and after rehabilitation. P<0.05 was considered as significant. The study findings demonstrated that the use of physical stimuli significantly increased the spine mobility, reduced subjective perception of pain measured according to the VAS and improved functional activity of the affected. The physical interventions were found to have beneficial effects on the selected parameters. [ABSTRACT FROM AUTHOR]

A characteristic of mast cells is the degranulation in response to various stimuli. Here we have investigated the effects of various physical stimuli in the human mast-cell line HMC-I. We have shown that HMC-1 express the transient receptor potential channels TRPVl, TRPV2 and TRPV4. In the whole-cell patch- clamp configuration, increasing mechanical stress applied to the mast cell by hydrostatic pressure (-30 to -90 crn H20 applied via the patch pipette) induced a current that could be inhibited by 10 µM of ruthenium red. This current was also inhibited by 20 µM SKF96365, an inhibitor that is among TRPV channels specific for the TRPV2. A characteristic of TRPV2 is its activation by high noxious temperature; temperatures exceeding 50 °C induced a similar ruthenium-red-sensitive current. As another physical stimulus, we applied laser light of 640 nm. Here we have shown for the first time that the application of light (at 48 mW for 20 min) induced an SKF96365-sensitive current. All three physical stimuli that led to activation of SKF96365-sensitive current also induced pronounced degranulation in the mast cells, which could be blocked by ruthenium red or SKF96365. The results suggest that TRPV2 is activated by the three different types of physical stimuli. Activation of TRPV2 allows Ca2+ ions to enter the cell, which in turn will induce degranulation. We, therefore, suggest that TRPV2 plays a key role in mast-cell degranulation in response to mechanical, heat and red laser-light stimulation. [ABSTRACT FROM AUTHOR]

Current engineering methods and their potential for use in cell-based research are reviewed. The basis of the suggested engineering methods is that real cellular responses can be assessed when the cells are under the same conditions as in vivo. Providing various conditions for this various engineering methodologies can be adopted. Three major factors should be considered when we apply bio-mimetic conditions to cells under in vitro culture conditions. They are the surface pattern and stiffness of the substrate, physical stimuli and neighboring cells. Various outcomes affected by those factors are introduced and reviewed. In particular, those outcomes from stem cell research have been reported. Even though some limitations of adopting those factors alone or combined still exist, the potential is now widely being recognized. The readers are kindly asked to consider those methodologies in relation to pharmaceutical research. [ABSTRACT FROM AUTHOR]

Recognition and acceptance of a suitable host plant by phytophagous insects requires the integration of visual, physical and chemical cues. The present study investigates the host cues that a specialist insect integrates to optimize oviposition decisions and whether these cues are weighted in a specific way. The study also determines whether the tomato fruit borer Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae), an important pest on Solanaceae in Brazil, shows a preference for oviposition sites that differ in physical and/or chemical cues. When styrofoam balls are provided as artificial fruits, N. elegantalis deposit significantly more eggs on rough artificial fruits than on smooth ones. Hexane fruit extracts applied to the artificial fruits stimulate female oviposition strongly. Physical and chemical cues also affect the oviposition of females when offered together. Furthermore, certain parts of the artificial fruits are prefered, irrespective of the presence of chemical cues. Both physical and chemical cues affect oviposition decisions; hence, the fruit borer relies on cues of different sensory modalities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultrasonication-light was developed as coupled physical stimuli for solvent-free RDRP. • Ultrasonication enabled effective process intensification for different photocatalytic pathway. • Good controls over polymerizations were achieved even at high conversion. • Current system enabled the polymerization towards "green" and sustainability. Focusing on energy-saving and environmentally-friendly polymerization engineering, ultrasonication and light were employed as coupled physical stimuli to regulate solvent-free reversible addition fragmentation chain transfer polymerization (RAFT), atom transfer radical polymerization (ATRP) and iodine transfer polymerization (ITP). The solvent-free polymerizations of (meth)acrylate under different conditions were performed with good control even at high monomer conversion (>90%), yielding polymers with low values of dispersity and retention of chain-end functionality. Kinetic experiments and mechanistic insights confirmed that light triggered different photocatalytic pathways (e.g. oxidative quenching cycle for RAFT, reductive quenching cycle for ATRP, photogenerated radical species for ITP) to initiate and mediate the solvent-free polymerizations and ultrasonication was used as an effective process intensification method to improve the diffusive of photocatalysts and their derivatives to alleviate the diffusional limitations for keeping good control up to high monomer conversion. This as-developed strategy is proved to be an efficient technology to produce well-defined polymers without complicated processes of products separation from solvent and residual monomer removal. [ABSTRACT FROM AUTHOR]

Acceptance of a potential host for oviposition by gravid female moths is believed to be predominantly determined by the physical and chemical cues on the substrate surface. We evaluated the effects of substrate physical and chemical stimuli on oviposition by the Indianmeal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), in a series of laboratory experiments. The experimental arenas were 5.7-liter plastic boxes that contained a single, uncovered 5-cm -diameter glass petri dish with either artificial substrates alone or artificial substrates applied with 0.1 g-equivalent of a hexane extract of wheat, Triticum aestivum L., or 10 g of wheat kernels. Presence of the chemical extract of wheat significantly increased P. interpunctella oviposition compared with physical stimuli without extract. A dish surface with spherical glass beads elicited significantly enhanced oviposition compared with surfaces with cheesecloth, filter paper, or sandpaper. Increasing the numbers of similar-sized extract-treated glass beads increased oviposition until a certain number of beads was reached, after which the oviposition remained constant. The diameter of the spherical glass beads, rather than the total surface area of beads presented, significantly influenced oviposition, with the 5-mm-diameter glass beads receiving the most eggs. P. interpunctella oviposition was also affected by the geometric shape of substrates, with ovoid shapes preferred over cuboid. These studies clearly show that semiochemical and physical cues are required to elicit maximum oviposition by P. interpunctella, and they suggest that ovipositing females prefer substrates with smooth, round or curved contours. [ABSTRACT FROM AUTHOR]