What Is the Real-life Experience of Older Adults on Smart Healthcare Technologies? An Exploratory Interview Study.

INTRODUCTION: Smart healthcare technologies exhibit the great potential to support older Hong Kong adults with their health problems. Although there are various smart healthcare technologies in the Hong Kong market, and some adoption predictors have been proposed and investigated, little is known about older users' views on and real-life experiences with these technologies. This exploratory study examined the experiences, functional needs and barriers of three kinds of smart healthcare technology (i.e., smart wearable devices, smart health monitors, and healthcare applications) with older adults in real-life. METHODS: A convenience sampling method was applied to recruit twenty-two older adults from the Hong Kong community. The interview was designed in semi-structured and conducted in a face-to-face setting. The content analysis was used to summarize the older adults' functional needs and barriers in real-life. RESULTS: We found older adults mainly applied SHCTs to address physical health, but there are few technological solutions for mental health in practice. There are four types of barriers in using smart healthcare technology. However, social support in Hong Kong community greatly help to reduce the barriers in technology use. Based on the findings, we discussed the possible solutions based on the social and technology perspective. CONCLUSION: Current technologies still could not fully address older adults needs for healthy aging and various barriers still hinder the actual adoption. By deeply understanding and considering the social context, technology innovation can facilitate the adoption of smart healthcare technology and promote a healthy aging society.

Synthetic Membraneless Droplets for Synaptic-Like Clustering of Lipid Vesicles.

In eukaryotic cells, the membraneless organelles (MLOs) formed via liquid-liquid phase separation (LLPS) are found to interact intimately with membranous organelles (MOs). One major mode is the clustering of MOs by MLOs, such as the formation of clusters of synaptic vesicles at nerve terminals mediated by the synapsin-rich MLOs. Aqueous droplets, including complex coacervates and aqueous two-phase systems, have been plausible MLO-mimics to emulate or elucidate biological processes. However, neither of them can cluster lipid vesicles (LVs) like MLOs. In this work, we develop a synthetic droplet assembled from a combination of two different interactions underlying the formation of these two droplets, namely, associative and segregative interactions, which we call segregative-associative (SA) droplets. The SA droplets cluster and disperse LVs recapitulating the key functional features of synapsin condensates, which can be attributed to the weak electrostatic interaction environment provided by SA droplets. This work suggests LLPS with combined segregative and associative interactions as a possible route for synaptic clustering of lipid vesicles and highlights SA droplets as plausible MLO-mimics and models for studying and mimicking related cellular dynamics.

The Influence of Anthropomorphic Cues on Patients' Perceived Anthropomorphism, Social Presence, Trust Building, and Acceptance of Health Care Conversational Agents: Within-Subject Web-Based Experiment.

BACKGROUND: The last decade has witnessed the rapid development of health care conversational agents (CAs); however, there are still great challenges in making health care CAs trustworthy and acceptable to patients. OBJECTIVE: Focusing on intelligent guidance CAs, a type of health care CA for web-based patient triage, this study aims to investigate how anthropomorphic cues influence patients' perceived anthropomorphism and social presence of such CAs and evaluate how these perceptions facilitate their trust-building process and acceptance behavior. METHODS: To test the research hypotheses, the video vignette methodology was used to evaluate patients' perceptions and acceptance of various intelligent guidance CAs. The anthropomorphic cues of CAs were manipulated in a 3×2 within-subject factorial experiment with 103 participants, with the factors of agent appearance (high, medium, and low anthropomorphic levels) and verbal cues (humanlike and machine-like verbal cues) as the within-subject variables. RESULTS: The 2-way repeated measures ANOVA analysis indicated that the higher anthropomorphic level of agent appearance significantly increased mindful anthropomorphism (high level>medium level: 4.57 vs 4.27; P=.01; high level>low level: 4.57 vs 4.04; P<.001; medium level>low level: 4.27 vs 4.04; P=.04), mindless anthropomorphism (high level>medium level: 5.39 vs 5.01; P<.001; high level>low level: 5.39 vs 4.85; P<.001), and social presence (high level>medium level: 5.19 vs 4.83; P<.001; high level>low level: 5.19 vs 4.72; P<.001), and the higher anthropomorphic level of verbal cues significantly increased mindful anthropomorphism (4.83 vs 3.76; P<.001), mindless anthropomorphism (5.60 vs 4.57; P<.001), and social presence (5.41 vs 4.41; P<.001). Meanwhile, a significant interaction between agent appearance and verbal cues (.004) was revealed. Second, the partial least squares results indicated that privacy concerns were negatively influenced by social presence (ß=-.375; t312=4.494) and mindful anthropomorphism (ß=-.112; t312=1.970). Privacy concerns (ß=-.273; t312=9.558), social presence (ß=.265; t312=4.314), and mindless anthropomorphism (ß=.405; t312=7.145) predicted the trust in CAs, which further promoted the intention to disclose information (ß=.675; t312=21.163), the intention to continuously use CAs (ß=.190; t312=4.874), and satisfaction (ß=.818; t312=46.783). CONCLUSIONS: The findings show that a high anthropomorphic level of agent appearance and verbal cues could improve the perceptions of mindful anthropomorphism and mindless anthropomorphism as well as social presence. Furthermore, mindless anthropomorphism and social presence significantly promoted patients' trust in CAs, and mindful anthropomorphism and social presence decreased privacy concerns. It is also worth noting that trust was an important antecedent and determinant of patients' acceptance of CAs, including their satisfaction, intention to disclose information, and intention to continuously use CAs.

Phase-separation facilitated one-step fabrication of multiscale heterogeneous two-aqueous-phase gel.

Engineering heterogeneous hydrogels with distinct phases at various lengths, which resemble biological tissues with high complexity, remains challenging by existing fabricating techniques that require complicated procedures and are often only applicable at bulk scales. Here, inspired by ubiquitous phase separation phenomena in biology, we present a one-step fabrication method based on aqueous phase separation to construct two-aqueous-phase gels that comprise multiple phases with distinct physicochemical properties. The gels fabricated by this approach exhibit enhanced interfacial mechanics compared with their counterparts obtained from conventional layer-by-layer methods. Moreover, two-aqueous-phase gels with programmable structures and tunable physicochemical properties can be conveniently constructed by adjusting the polymer constituents, gelation conditions, and combining different fabrication techniques, such as 3D-printing. The versatility of our approach is demonstrated by mimicking the key features of several biological architectures at different lengths: macroscale muscle-tendon connections; mesoscale cell patterning; microscale molecular compartmentalization. The present work advances the fabrication approach for designing heterogeneous multifunctional materials for various technological and biomedical applications.

Partitioning-Induced Isolation of Analyte and Analysis via Multiscaled Aqueous Two-Phase System.

Most fluorescence-based bioanalytical applications need labeling of analytes. Conventional labeling requires washing to remove the excess fluorescent labels and reduce the noise signals. These pretreatments are labor intensive and need specialized equipment, hindering portable applications in resource-limited areas. Herein, we use the aqueous two-phase system (ATPS) to realize the partitioning-induced isolation of labeled analytes from background signals without extra processing steps. ATPS is formed by mixing two polymers at sufficiently high concentrations. ATPS-based isolation is driven by intrinsic affinity differences between analytes and excess labels. To demonstrate the partitioning-induced isolation and analysis, fluorescein isothiocyanate (FITC) is selected as the interfering fluorophore, and a monoclonal antibody (IgG) is used as the analyte. To optimize ATPS compositions, different molecular weights and mass fractions of polyethylene glycol (PEG) and dextran and different phosphate-buffered saline (PBS) concentrations are investigated. Various operational scales of our approach are demonstrated, suggesting its compatibility with various bioanalytical applications. In centimeter-scale ATPS, the optimized distribution ratios of IgG and FITC are 91.682 and 0.998 using PEG 6000 Da and dextran 10,000 Da in 10 mM PBS. In millimeter-scale ATPS, the analyte is enriched to 6.067 fold using 15 wt % PEG 35,000 Da and 5 wt % dextran 500,000 Da in 10 mM PBS. In microscale ATPS, analyte dilutions are isolated into picoliter droplets, and the measured fluorescence intensities linearly correlated with the analyte concentrations (R2 = 0.982).

Tuning Material States and Functionalities of G-Quadruplex-Modulated RNA-Peptide Condensates.

RNA encodes sequence- and structure-dependent interactions to modulate the assembly and properties of biomolecular condensates. RNA G-quadruplexes (rG4s) formed by guanine-rich sequences can trigger the formation of liquid- or solid-like condensates that are involved in many aberrant phase transitions. However, exactly how rG4 motifs modulate different phase transitions and impart distinct material properties to condensates is unclear. Here, using RNA oligonucleotides and cationic peptides as model systems, we show that RNA-peptide condensates exhibit tunability in material properties over a wide spectrum via interactions arising from rG4 folding/unfolding kinetics. rG4-containing oligonucleotides formed strong pairwise attraction with peptides and tended to form solid-like condensates, while their less-structured non-G4 mutants formed liquid-like droplets. We find that the coupling between rG4 dissociation and RNA-peptide complex coacervation triggers solid-to-liquid transition of condensates prior to the complete unfolding of rG4s. This coupling points to a mechanism that material states of rG4-modulated condensates can be finely tuned from solid-like to liquid-like by the addition of less-structured RNA oligonucleotides, which have weak but dominant binding with peptides. We further show that the tunable material states of condensates can enhance RNA aptamer compartmentalization and RNA cleavage reactions. Our results suggest that condensates with complex properties can emerge from subtle changes in RNA oligonucleotides, contributing ways to treat dysfunctional condensates in diseases and insights into prebiotic compartmentalization.

Dynamic Assembly of Viscoelastic Networks by Aqueous Liquid-Liquid Phase Separation and Liquid-Solid Phase Separation (AqLL-LS PS2 ).

Living cells comprise diverse subcellular structures, such as cytoskeletal networks, which can regulate essential cellular activities through dynamic assembly and synergistic interactions with biomolecular condensates. Despite extensive efforts, reproducing viscoelastic networks for modulating biomolecular condensates in synthetic systems remains challenging. Here, a new aqueous two-phase system (ATPS) is proposed, which consists of poly(N-isopropylacrylamide) (PNIPAM) and dextran (DEX), to construct viscoelastic networks capable of being assembled and dissociated dynamically to regulate the self-assembly of condensates on-demand. Viscoelastic networks are generated using liquid-liquid phase-separated DEX droplets as templates and the following liquid-to-solid transition of the PNIPAM-rich phase. The resulting networks can dissolve liquid fused in sarcoma (FUS) condensates within 5 min. This work demonstrates rich phase-separation behaviors in a single ATPS through incorporating stimuli-responsive polymers. The concept can potentially be applied to other macromolecules through other stimuli to develop materials with rich phase behaviors and hierarchical structures.

Characterization and Functional Studies of a Novel Depolymerase Against K19-Type Klebsiella pneumoniae.

Carbapenem-resistant Klebsiella pneumoniae (CRKP), a pathogen that causes severe nosocomial infections and yields a high mortality rate, poses a serious threat to global public health due to its high antimicrobial resistance. Bacteriophages encode polysaccharide-degrading enzymes referred to as depolymerases that cleave the capsular polysaccharide (CPS), one of the main virulence factors of K. pneumoniae. In this study, we identified and characterized a new capsule depolymerase K19-Dpo41 from K. pneumoniae bacteriophage SH-KP156570. Our characterization of K19-Dpo41 demonstrated that this depolymerase showed specific activities against K19-type K. pneumoniae. K19-Dpo41-mediated treatments promoted the sensitivity of a multidrug-resistant K19-type K. pneumoniae strain to the bactericidal effect of human serum and significantly increased the survival rate of Galleria mellonella infected with K19-type K. pneumoniae. Our results provided strong primary evidence that K19-Dpo41 was not only effective in capsular typing of K19-type K. pneumoniae but promising in terms of developing new alternative therapeutic strategies against K19-type CRKP infections in the future.

Aquabots.

Soft robots, made from elastomers, easily bend and flex, but deformability constraints severely limit navigation through and within narrow, confined spaces. Using aqueous two-phase systems we print water-in-water constructs that, by aqueous phase-separation-induced self-assembly, produce ultrasoft liquid robots, termed aquabots, comprised of hierarchical structures that span in length scale from the nanoscopic to microsciopic, that are beyond the resolution limits of printing and overcome the deformability barrier. The exterior of the compartmentalized membranes is easily functionalized, for example, by binding enzymes, catalytic nanoparticles, and magnetic nanoparticles that impart sensitive magnetic responsiveness. These ultrasoft aquabots can adapt their shape for gripping and transporting objects and can be used for targeted photocatalysis, delivery, and release in confined and tortuous spaces. These biocompatible, multicompartmental, and multifunctional aquabots can be readily applied to medical micromanipulation, targeted cargo delivery, tissue engineering, and biomimetics.

Non-associative phase separation in an evaporating droplet as a model for prebiotic compartmentalization.

The synthetic pathways of life's building blocks are envisaged to be through a series of complex prebiotic reactions and processes. However, the strategy to compartmentalize and concentrate biopolymers under prebiotic conditions remains elusive. Liquid-liquid phase separation is a mechanism by which membraneless organelles form inside cells, and has been hypothesized as a potential mechanism for prebiotic compartmentalization. Associative phase separation of oppositely charged species has been shown to partition RNA, but the strongly negative charge exhibited by RNA suggests that RNA-polycation interactions could inhibit RNA folding and its functioning inside the coacervates. Here, we present a prebiotically plausible pathway for non-associative phase separation within an evaporating all-aqueous sessile droplet. We quantitatively investigate the kinetic pathway of phase separation triggered by the non-uniform evaporation rate, together with the Marangoni flow-driven hydrodynamics inside the sessile droplet. With the ability to undergo liquid-liquid phase separation, the drying droplets provide a robust mechanism for formation of prebiotic membraneless compartments, as demonstrated by localization and storage of nucleic acids, in vitro transcription, as well as a three-fold enhancement of ribozyme activity. The compartmentalization mechanism illustrated in this model system is feasible on wet organophilic silica-rich surfaces during early molecular evolution.

Effect of cholesterol on the fluidity of supported lipid bilayers.

The lateral mobility serves as a key function of the cell membrane and can be regulated by the cholesterol. Here supported lipid bilayers were used to quantitatively analyse the influence of cholesterol on the fluidity of lipid bilayer in the environments with and without an electric field. We observed that with the increase of cholesterol proportion (0-30 mol%), the diffusion coefficient of DOPC lipid bilayer gradually decreased from 1.30 ± 0.15 µm2 s-1 to 0.28 ± 0.13 µm2 s-1, where as that of DPPC lipid bilayer increased slightly from ∼0 to 0.45 ± 0.18 µm2 s-1. We then showed that cholesterol also regulated the movement of charged lipids in the bilayer in the electric field. The migration rate of charged lipids in the DOPC bilayers slowed down as the cholesterol increased. The clarification of the dose-effect relationship of cholesterol for the bidirectional regulating effect on the mobility of lipid bilayer will extend applications of supported lipid bilayers as the model of cell membrane.

Healthcare at Your Fingertips: The Acceptance and Adoption of Mobile Medical Treatment Services among Chinese Users.

Mobile health (mHealth) services have recently been receiving increasing attention. However, there is a lack of knowledge about how users accept and adopt mobile medical treatment (MMT) services, some of the most promising mHealth services that aim to extend the patient-physician relationship beyond the conventional clinic environment. To fill this research gap, this study proposes a research model for predicting consumers' acceptance behavior toward MMT services based on the Technology Acceptance Model (TAM). A survey was conducted among 303 Chinese MMT service users to evaluate the proposed model and relevant hypotheses using partial least squares. Several key findings were summarized from the results: (1) the attitude toward using MMT, technology anxiety, and trust are significantly associated with users' behavioral intention to use MMT services; (2) the perceived ease of use, perceived usefulness, and trust significantly influence users' attitude toward using MMT services; (3) the perceived interactivity, perceived personalization, and privacy concerns have significant impacts on users' perceptions of ease of use, usefulness, and trust toward MMT services. The current findings have both theoretical and practical implications that may guide practitioners and researchers to better understand consumers' acceptance of MMT services.

Phospholipid Self-Assemblies Shaped Like Ancient Chinese Coins for Artificial Organelles.

Phospholipid self-assemblies are ubiquitous in organisms. Nonspherical lipid-based proto-organelles bear the merits with structures similar to real organelles. It is still a challenge to mimic mass transport between organelles inside cells. Herein, unusual phospholipid self-assemblies shaped like ancient Chinese coins (ACC) were discovered by the recrystallization of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine in an ethanol/water solution from 50 to 25 °C with a certain cooling rate. Their diameter and the ratio of the square edge to the disk diameter were controlled by varying ethanol percentage, lipid concentration, and cooling rate. The ACC-shaped phospholipid bicelles expanded to stacked cisterna structures in pure water, which were regarded as artificial organelles. Mass transport among organelles in a cell was mimicked via the membrane fusion of vesicle shuttles and artificial organelles, which induced cascade enzyme reactions inside artificial organelles. The ACC-shaped phospholipid assemblies provide nice platforms for the studies of cell biology and bottom-up synthetic biology.

Programmed magnetic manipulation of vesicles into spatially coded prototissue architectures arrays.

In nature, cells self-assemble into spatially coded tissular configurations to execute higher-order biological functions as a collective. This mechanism has stimulated the recent trend in synthetic biology to construct tissue-like assemblies from protocell entities, with the aim to understand the evolution mechanism of multicellular mechanisms, create smart materials or devices, and engineer tissue-like biomedical implant. However, the formation of spatially coded and communicating micro-architectures from large quantity of protocell entities, especially for lipid vesicle-based systems that mostly resemble cells, is still challenging. Herein, we magnetically assemble giant unilamellar vesicles (GUVs) or cells into various microstructures with spatially coded configurations and spatialized cascade biochemical reactions using a stainless steel mesh. GUVs in these tissue-like aggregates exhibit uncustomary osmotic stability that cannot be achieved by individual GUVs suspensions. This work provides a versatile and cost-effective strategy to form robust tissue-mimics and indicates a possible superiority of protocell colonies to individual protocells.

A Uniaxial Compression Experiment with CO2-Bearing Coal Using a Visualized and Constant-Volume Gas-Solid Coupling Test System.

Injecting carbon dioxide (CO2) into a deep coal seam is of great significance for reducing the concentration of greenhouse gases in the atmosphere and increasing the recovery of coalbed methane. A visualized and constant-volume gas-solid coupling system is introduced here to investigate the influence of CO2 sorption on the physical and mechanical properties of coal. Being able to keep a constant volume and monitor the sample using a camera, this system offers the potential to improve instrument accuracy and analyze fracture evolution with a fractal geometry method. This paper provides all steps to perform a uniaxial compression experiment with a briquette sample in different CO2 pressures with the gas-solid coupling test system. A briquette, cold-pressed by raw coal and sodium humate cement, is loaded in high-pressure CO2, and its surface is monitored in real-time using a camera. However, the similarity between the briquette and the raw coal still needs improvement, and a flammable gas such as methane (CH4) cannot be injected for the test. The results show that CO2 sorption leads to peak strength and elastic modulus reduction of the briquette, and the fracture evolution of the briquette in a failure state indicates fractal characteristics. The strength, elastic modulus, and fractal dimension are all correlated with CO2 pressure but not with a linear correlation. The visualized and constant-volume gas-solid coupling test system can serve as a platform for experimental research about rock mechanics considering the multifield coupling effect.

Topological Defect-Driven Buckling of Phospholipid Bicelles to Cones for Micromotors with Modulated Heading Pathways.

Topological defects are crucial to the shaping of the crystalline membrane systems such as lipid bilayers, virus capsids, and graphene as well as the arrangement of cells in tissues. In a typical case, the introduction of disclination defects elastically buckles the crystalline membranes into conical shapes. However, how planar membranes transform to cones triggered by disclinations is still rarely observed in the experiments. Herein, we experimentally observe the transformation from phospholipid bicelles to cones in response to disclinations. During the transformation process, the wall thickness increases, while the conical generatrix length remains the same with respect to the radius of bicelles. The cones with apex angles of 112.8°, 83.6°, 60°, 39°, and 19.2° are observed when 1, 2, 3, 4, and 5 pentagon defects are introduced, respectively. Monodispersed microcones are obtained by adjusting aging temperature and time. These microcones are then used as templates to form platinum conical micromotors with open tips or closed tips, which display different heading directions in H2O2 solution. Our work provides a shape evolution pathway of planar membranes in response to disclinations. The homogeneous microcones can find wide applications in micromotors fabrication, the study of curvature-dependent processes, and the formation of advanced materials.

One-pot green synthesis of bimetallic hollow palladium-platinum nanotubes for enhanced catalytic reduction of p-nitrophenol.

Bimetallic alloy nanostructures have garnered much attention due to their unique performances in catalytic processes. However, decline in catalytic activity over the life span has been a protracted limitation, ascribed largely to the aggregation or dissociation of particles and still remains a challenge for manufacturing bimetallic nanostructures of sufficient stability. Herein, a surfactant- and solvent-free greener strategy is presented for the fabrication of bimetallic palladium-platinum (PdPt) nanotubes (NTs), deploying lipid tubules as template and ascorbic acid as a reducing agent; the ensuing NTs comprise crystalline tubal nanostructures of ∼12 µm length, ∼500 nm cross-sectional diameter, and ∼57 nm tube wall thickness. When used for the catalytic reduction of p-nitrophenol (PNP), the PdPt NTs delivered improved kinetic apparent rate constants (kapp) compared to Pt NTs (0.5 min-1vs. 0.2 min-1). Moreover, the NTs demonstrated high stability when used over multiple catalytic cycles thus opening up new potential routes for the fabrication of alloy NTs using lipid tubules as templates.

Giant Unilamellar Vesicle Microarrays for Cell Function Study.

Giant unilamellar vesicles (GUVs) are widely used as artificial cell models which contribute to elucidate fundamental questions on origin of life and cell functions. Herein, the GUV microarrays were developed using a point-to-plane electrode system combined with microcontact stripping technique. The biomolecules (DNA, etc.) were selectively encapsulated only inside patterned GUVs. The GUV arrays were used to investigate species mass transport across cell membranes. The release of carboxyfluorescein from GUVs showed a melittin concentration dependent manner. The diffusion coefficient were 0.37 × 10-11, 0.36 × 10-11, 0.54 × 10-11, 1.10 × 10-11, 1.74 × 10-11, 2.31 × 10-11, and 3.62 × 10-11 m2/s for 0, 0.5, 1.0, 2.0, 3.0, 4.0, and 5.0 µM melittin, respectively. The GUV arrays were also a good platform for cell metabolism investigation. Horseradish peroxidase (HRP) loaded GUV microarrays were used to mimic internal metabolism by exposing them to the substrates of H2O2 and o-PD to yield fluorescent 2,3-diaminophenazine (2,3-DAP).The proposed GUV arrays have great potential in cell function studies.

Self-Assembled Rough Endoplasmic Reticulum-Like Proto-Organelles.

Nature has evolved elaborate, dynamic organelle morphologies for optimal organelle functions. Among them, cisternae stacks are the universal structure for most organelles. However, compared with the well-studied spherical cell/organelle membrane mimic, the fabrication of the ubiquitously present cisternal organelle-like membrane structures for organelle mimic remains a challenging task. Herein, rough endoplasmic reticulum (RER)-like helicoidal cisternae stacks were assembled to mimic the enzyme crowded environment in spatially confined RER cisternae. RER-like single helicoid, multiple helicoids, and secondary helix are all observed. Membrane electrostatics drives their formation and controls the percentages, which indicates the possible role of membrane electrostatics in RER shaping. The organelle-like cisternae stacks can reversibly expand and compress, which provides modulated crowded or de-crowded enzyme environment for biochemical reactions. This work provides advanced membrane models, and novel mechanisms for organelle shaping and helicoids formation, and holds great potential in biomimetics, cell biology, and advanced materials design.

Deformation of giant unilamellar vesicles under osmotic stress.

Biological membrane plays an important role in maintaining an osmotic equilibrium between the cytoplasm and the extracellular solution of cells. Here, the giant unilamellar vesicles (GUVs) as cell models were used to investigate the effect of osmotic stress on phospholipid membranes. The deformation of GUVs, including inward budding and outward budding, was systematically investigated by the osmotic press from glucose, sucrose, LiCl, and KCl solutions. The permeability (P) of DMPC, DMPC/10 mol% Chol GUVs, DMPC/25 mol% Chol GUVs, and DMPC/40 mol% Chol GUVs in glucose, sucrose, LiCl, and KCl solutions were all obtained. The P value decreases with the addition of more cholesterol in the bilayer. The monovalent cations caused higher permeability of lipid bilayer membranes due to their combination with phospholipids. The molar flux of water (J) value was found to be the key factor for determining the deformation state from mainly inward budding to mainly outward budding. The findings in this paper may help us to understand cell transformation triggered with osmotic stress.