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Roadmapping has long been regarded as a practical tool for supporting decision-making for science and technology innovation and it has received recent attention for its potential use in responses to uncertainty. Indeed, roadmapping enables forward-looking strategy making and thus helps to reduce uncertainty. Accordingly, numerous studies have been conducted to propose new approaches to roadmapping for a wide range of contexts, including the data-driven and expert-based approaches. Although these two main approaches have distinct advantages and disadvantages, few previous studies have focused on how to integrate them into roadmapping to better support decision-making related to science and technology innovation. To address this research gap, this study investigated how to integrate data-driven approaches with expert insights during roadmapping. For this purpose, a workshop-based roadmapping method was combined with data-driven methods to test this approach in the context of technology planning for the automobile industry. An ethnographic approach was used to collect data on when, where, and how data analysis must be conducted to support experts’ discussions. The research findings open a discussion regarding how to integrate data-driven methods with expert insights during roadmapping based on the trade-offs between the two types of data, that is, hard data for data-driven methods and soft data from expert insights, and suggest possible opportunities for future roadmapping developments.

Injectable biomaterials alone may alter local tissue responses, including inflammatory cascades and matrix production (e.g. stimulatory dermal fillers are used as volumizing agents that induce collagen production). To expand upon the available material compositions and timing of presentation, a tunable hyaluronic acid (HA) and poly(lactide-co-glycolide) (PLGA) microsphere composite system was formulated and assessed in subcutaneous and cardiac tissues. HA functionalized with hydroxyethyl methacrylate (HeMA) was used as a precursor to injectable and degradable hydrogels that carry PLGA microspheres (∼50 μm diameter) to tissues, where the HA hydrogel degradation (∼20 or 70 days) and quantity of PLGA microspheres (0–300 mg ml−1) are readily varied. When implanted subcutaneously, faster hydrogel degradation and more microspheres (e.g. 75 mg ml−1) generally induced more rapid tissue and cellular interactions and a greater macrophage response. In cardiac applications, tissue bulking may be useful to alter stress profiles and to stabilize the tissue after infarction, limiting left ventricular (LV) remodeling. When fast degrading HeMA–HA hydrogels containing 75 mg ml−1 microspheres were injected into infarcted tissue in sheep, LV dilation was limited and the thickness of the myocardial wall and the presence of vessels in the apical infarct region were increased ∼35 and ∼60%, respectively, compared to empty hydrogels. Both groups decreased volume changes and infarct areas at 8 weeks, compared to untreated controls. This work illustrates the importance of material design in expanding the application of tissue bulking composites to a range of biomedical applications.

The stratum corneum (SC), composed of corneocytes and intercellular lipid membranes, is the outermost layer of the epidermis, and its main function is the regulation of water loss from the skin. The major components of the SC lipid membranes are ceramides (CER), cholesterol (CHOL), and free fatty acids (FFA), which are organized in multilamellar structures between corneocytes. The intercellular SC lipid membrane is believed to provide the main pathway for the transport of water and other substances through the skin. While changes in the composition of the SC lipid membranes have been shown to affect the organization of the lipid molecules, little is known about the effect of compositional changes on their water permeability. In this work, we study the effect of membrane composition on the water permeability of model SC lipid membranes using a quartz crystal microbalance with dissipation monitoring (QCM-D). The QCM-D method enables the direct determination of the diffusivity (D), solubility (S), and permeability (P) of water through the model SC lipid membranes. We find that D and S weakly depend on the chain length of saturated fatty acids, while P shows no significant dependence. In contrast, the saturation level of free fatty acids and the structure of ceramide have significant influence on D and S, respectively, resulting in significant changes in P. By taking advantage of the dissipation monitoring capability of the QCM-D at multiple overtones, we find that the shear modulus (G) of the SC lipid membranes depends on its composition and decreases upon water absorption by the membranes.

The generation of near-infrared (NIR)-sensitive microcapsules is presented and it is demonstrated that the release properties of these microcapsules can be tailored by controlling their morphology. A biocompatible polymer, poly(DL-lactic-co-glycolic)acid (PLGA) is used to form hollow microcapsules from monodisperse water-in-oil-in-water (W/O/W) double emulsions. Both the composition of PLGA and the oil phase of W/O/W double emulsions significantly affect the morphology of the subsequently formed microcapsules. PLGA microcapsules with vastly different morphologies, from spherical to “snowman-like” capsules, are obtained due to changes in the solvent quality of the oil phase during solvent removal. The adhesiveness of the PLGA-laden interface plays a critical role in the formation of snowman-like microcapsules. NIR-sensitive PLGA microcapsules are designed to have responsive properties by incorporating Au nanorods into the microcapsule shell, which enables the triggered release of encapsulated materials. The effect of capsule morphology on the NIR responsiveness and release properties of PLGA microcapsules is demonstrated.

This paper presents the generation of amphiphilic Janus bubbles and their behavior at an air–water interface. Janus bubbles are generated by selectively depositing gold onto one side of dried nanoparticle-shelled bubbles. To generate nanoparticle-shelled bubbles that can withstand drying without significant changes in their structure, it is critical to control the ratio of bubble radius to shell thickness using a microfluidic technique. It is observed that the behavior of Janus bubbles at an air–water interface is very different from that of unmodified nanoparticle-shelled bubbles. Interfacial assembly of amphiphilic Janus bubbles shows that they interact with one another via long-ranged attractions. The origin of this long-ranged attraction is quadrupolar capillary interactions due to the undulation of the three-phase contact line around the Janus boundary. The interparticle forces between interface-trapped Janus bubbles are determined using a particle tracking method. The shape of the deformed air–water interface around Janus bubbles is directly observed as well as the orientation of Janus bubbles using a gel-trapping technique. These observations verify that the air–water interface is pinned around the boundary between the two hemispheres and that the chemical heterogeneity of this boundary leads to irregular contact line around Janus bubbles.

Stimuli-responsive materials undergo structural changes in response to an external trigger (i.e., pH, heat, or light). This process has been previously used for a range of applications in biomedicine and microdevices and has recently gained considerable attention in controlled drug release. Here, we use a near-infrared (NIR) light responsive polymer-nanorod composite whose glass transition temperature (T(g)) is in the range of body temperature to control and enhance the release of a small-molecule drug (800 Da). In addition to increased temperature and resulting changes in molecule diffusion, the photothermal effect (conversion of NIR light to heat) adjusts the composite above the T(g). Specifically, at normal body temperature (TT(g)), the structure is glassy and release is limited, whereas when TT(g), the polymer is rubbery and release is enhanced. We applied this heating system to trigger release of the chemotherapeutic drug doxorubicin from both polymer films and microspheres. Multiple cycles of NIR exposure were performed and demonstrated a triggered and stepwise release behavior. Lastly, we tested the microsphere system in vitro, reporting a ∼90% reduction in the activity of T6-17 cells when the release of doxorubicin was triggered from microspheres exposed to NIR light. This overall approach can be used with numerous polymer systems to modulate molecule release toward the development of unique and clinically applicable therapies.

We investigate the mechanical properties of layers of the protein beta-lactoglobulin during their formation at the air-water interface using a combination of passive and active microrheological techniques. The passive microrheology, which employs multiple particle tracking measurements using spherical colloids, indicates that the interfacial rheology evolves over time through three stages as protein adsorbs at the interface: (i) an increase in viscosity, (ii) a period of spatial heterogeneity in which the interface contains elastic and viscous regions, and (iii) the development of a uniformly rigid elastic film. Varying solution pH between pH = 5.2, the isoelectric point of beta-lactoglobulin, and pH = 7.0 has no qualitative effect on this mechanical evolution. The active microrheology, which employs ferromagnetic nanowires rotating in response to magnetic torques, similarly shows an increasing interfacial viscosity at early times and evidence of mechanical heterogeneity at intermediate times. However, at late times, the nanowire mobility becomes strongly pH dependent. For pH = 5.2, the layer responds as a rigid elastic film to the stress imposed by the wire. For pH = 7.0, it displays a viscous response that contrasts with the passive measurements. We associate this contrast with a nonlinear response to the wire at late times that reflects a low yield stress of the film at higher pH. This ability to compare passive and active measurements demonstrates the advantage of applying multiple microrheological methods to resolve ambiguity in any single approach.

We have two concepts of Douglas spaces and Lands-berg spaces as generalizations of Berwald spaces. S. Bacso gave the definition of a weakly-Berwald space [2] as another generalization of Berwald spaces. In the present paper, we find the conditions that the Finsler space with an ()-metric be a weakly-Berwald space and the Finsler spaces with some special ()-metrics be weakly-Berwald spaces, respectively.

Silver nanoparticles were prepared by reducing silver ions in the hexagonal phase formed by Triton X-100 in aqueous solution. Triton X-100 molecules have been used to form the hexagonal phase in aqueous solution as well as to reduce the silver ions into silver atoms. The hexagonal phase hindered the growth and aggregation of particles. The microstructure of the hexagonal phase was investigated by polarizing microscopy, 2 H NMR spectroscopy and small-angle X-ray diffraction. At the initial stage of the reaction, silver particles prepared in the hexagonal phase exhibited a size of 1–7 nm. As the reaction proceeded, particles grew up to about 30 nm as determined by transmission electron microscopy (TEM). The formation rate of silver particles was investigated by UV–Visible spectroscopy. It was found that the reaction temperature was an important factor for the rate of particle formation. With TEM, it was confirmed that surfactant aggregates, which have flexible structures, could not absolutely prevent particles from growing and aggregating. But, the results of polarizing microscopy, 2 H NMR spectroscopy and X-ray diffraction exhibited that the growth of particles could not cause a deformation of the original structure (hexagonal phase), which was employed as the reaction medium.

In this study, Y(2)O(3):Eu luminescent nanoparticles were prepared by precipitation of aqueous yttrium nitrate/europium nitrate solution using ammonium hydroxide in the reverse microemulsions based on polyoxyethylene (5) nonylphenyl ether/polyoxyethylene (9) nonylphenyl ether, cyclohexane, and water. With Eu-doped Y(2)O(3) nanoparticles obtained, particle size, shape, chemical composition, crystalline formation rate, crystallinity, and photoluminescence were measured and compared with those of particles formed by a bulk precipitation method. The nanoparticles synthesized in microemulsion showed a narrow size distribution, spherical shape, fast crystalline formation rate, high crystallinity, and strong photoluminescence. This stronger photoluminescence of particles formed in a microemulsion might be attributed to more densely packed particles with very few voids and higher crystallinity at a relatively low temperature than those synthesized through a bulk precipitation method. Copyright 2000 Academic Press.

The main objective of this paper was to investigate the effect of transmission of force on bone cells that were attached to a deformable membrane. We functionalized a silastic membrane that measured 0.005 inches thickness and coated it with an extra cellular matrix (ECM) protein, fibronectin (FN). MC3T3-E1 osteoblast-like cells were cultured on the functionalized FN-coated membrane after which cell attachment and proliferation were evaluated. We observed an immediate attachment and proliferation of the bone cells on the functionalized membrane coated with FN, after 24 hours. Upon application of a mechanical force to cells cultured on the functionalized silicone membrane in the form of a dynamic equibiaxial strain, 2% magnitude; at 1-Hz frequency for 2 h, the osteoblast cells elicited slightly elevated phalloidin fluorescence, suggesting that there was reorganization of the cytoskeleton. We concluded from this preliminary data obtained that the engineered surface transduced applied mechanical forces directly to the adherent osteoblast cells via integrin binding tripeptide receptors, present in the FN molecules, resulting in the enhanced cellular attachment and proliferation.

We introduce a microfluidic approach to generating monodisperse, stable nanoparticle-shelled bubbles using air-in-oil-in-water (A/O/W) compound bubbles as templates. The oil phase of the A/O/W compound bubbles comprises a volatile organic solvent and a hydrophobic silica nanoparticle. Upon evaporation of the organic solvent, the nanoparticles in the oil layer form a stiff shell at the air-water interface, which drastically enhances the stability of the bubbles against dissolution and coarsening. On the basis of this approach, we demonstrate that it is also possible to generate functional bubbles stabilized by composite shells that are composed of mixtures of hydrophobic materials and nanoparticles with unique properties.

We study the microscopic mechanical response of colloidal gels by manipulating single probe particles within the network. For this work, we use a refractive index and density-matched suspension of polymethylmethacrylate (PMMA) particles with nonadsorbing polymer: polystyrene. As the polymer concentration increases, a dynamically arrested, space-filling network is formed, exhibiting structural transitions from a clusterlike to a more homogeneous stringlike gel phase, consistent with observations by Dibble and co-workers [C. J. Dibble, M. Kogan, and M. J. Solomon, Phys. Rev. E 74, 041403 (2006)]. In a gel, probe particles are oscillated with an optical trap, creating the local strain field in the network. We find that the micromechanics correlate strongly with the gel structure. At high polymer concentration, the average deformation field decays as $1/r$ to a distance quite close to the probe particle, as expected for a purely elastic material. In contrast, at lower polymer concentrations, gels exhibit anomalous strain fields in the near field; the strain plateaus, indicating that many particles move together with the probe. By rescaling the probe size in the theoretical model, we obtain a micromechanical gel correlation length, which is consistent with the structural difference in terms of ``clusterlike'' and ``stringlike.''

Core-shell silica particles, with a diameter of 1.5 μm, containing a dye fluorescein isothiocyanate (FITC), are synthesized by the hydrolysis and condensation of tetraethylorthosilicate (TEOS). Sodium dodecyl sulfate (SDS) is added to synthesize fluorescent core particles with the diameter of approximately 1 μm. In the addition of SDS, the surface charge reduced by counterions (Na + ) of the surfactant leads to a higher degree of aggregation of the primary particles and the formation of larger secondary particles. The particle growth kinetics confirms the aggregation growth model for the synthesis of monodisperse silica particles, and also shows the dependence of final particle size on colloidal stability resulting from the addition of SDS. Light and X-ray scattering data reveal that the final particles have compactly packed structures with smooth surfaces. The seeded growth technique is then used to form a silica shell layer on the fluorescent core. The added amount of water and NH 4 OH has significant effects on shell formation. Finally, the final core-shell silica particles are modified by chemisorption of octadecanol at the surface to be dispersed in organic solvents. Octadecyl-coated silica particles are sterically stabilized in silica index-matching solvents such as chloroform and hexadecane to directly image separate particles using confocal microscopy. In chloroform, the organophilic silica particles disperse well, whereas in hexadecane they form a volume-filling gel structure at room temperature.

Retinol, a cosmetic ingredient, was entrapped within inorganic microspheres obtained from sol-gel reaction of TEOS in o/w/o multiple emulsions as microreactors. In o/w/o multiple emulsions, the retinol was emulsified as an internal oil phase in a aqueous solution of 3.0 wt% Tween 20 prior to emulsification into an external oil phase. The multiple emulsions appeared to be stable enough in the presence of HPC polymer in the external oil phase. In sol-gel reaction, the hydrolysis and condensation rate of TEOS were greatly dependent upon the catalyst and the molar ratio of H(2)O to TEOS (R(W)). In this study, sphere-like microspheres entrapping retinol were best formed with the addition of NH(4)OH as a catalyst when the concentration of TEOS was at the R(W) value of 4. Microspheres obtained under these conditions were 15-40mgr;m with very dense surfaces containing a few globules 1.17-2.35mgr;m. Also, they showed the slower release of retinol into the external ethanol phase and higher loading and encapsulation efficiency. Copyright 2001 Academic Press.

We employ the Brownian motion of spherical colloids to investigate the microrheology of layers of the protein β-lactoglobulin adsorbing at a decane–water interface. Using an experimental design in which the protein concentration in the aqueous subphase increases in a diffusion-limited manner, we obtain a time-resolved characterization of the interfacial rheology. After undergoing a period of increasing interfacial viscosity, the layers become viscoelastic with a rheology that indicates an approach to a sol–gel transition. This evolution, which depends on subphase pH, contrasts in several significant ways with layer formation by β-lactoglobulin at an air–water interface. Comparison of the diffusivity of colloids of two sizes as the interfacial viscosity increases illustrates the transformation in particle mobility from a three-dimensional character in which the surrounding bulk fluids dominate to a two-dimensional form dictated by the drag from the interfacial layer. This transformation is similarly revealed in the two-point correlations of the particle motion, which show a change in spatial dependence indicating a crossover from three-dimensional to two-dimensional hydrodynamics.

We measured the materials properties of polymersomes templated by double emulsions. Using micropipette aspiration, we verified the unilamellarity of fluid membranes consisting of PEO30-b-PBD46 diblock copolymers. In addition, we used micropipette aspiration to both track and verify solvent removal from double emulsion-templated polymersomes.

We study the stability of polymer-shelled bubbles with controlled dimensions generated from air-in-oil-in-water (A/O/W) compound bubbles. We show that the ratio of the shell thickness to bubble radius is critical in generating un-deformed polymer-shelled bubbles from A/O/W compound bubbles. In addition, the effects of shell stiffness and encapsulated gas on bubble stability are also investigated.

The meningiomas are slowly growing tumors arising from meningoepithelial cells and they generally occur throughout the craniospinal axis. Meningiomas extending to the middle ear cavity are uncommom and these patients complain of otologic symptoms such as hearing loss, ear fullness, or otorrhea. Clinical findings frequently suggest otitis media resistant to conventional treatments, thereby facilitating misdiagnosis. CT and MRI of the temporal bone are essential and important for the radiologic differential diagnosis with other tumors. The ideal treatment of these tumors is a total surgical removal. In this report, we describe 2 cases of middle ear meningioma originating from middle and posterior cranial fossas with a review of the literatures. (Korean J Otorhinolaryngol-Head Neck Surg 2009;52:184-8)

Y 2 O 3 :Eu luminescent particles were synthesized by the reaction between aqueous yttrium nitrate/europium nitrate salts and ammonium hydroxide solution by bulk precipitation and in the reverse microemulsion composed of NP-5/NP-9, cyclohexane, and water. Compared with Y 2 O 3 :Eu luminescent particles formed by the bulk precipitation method, the particles prepared in microemulsion showed a narrower size distribution, spherical shape, smaller size (20-30 nm), higher crystallinity, and stronger photoluminescence. Also, Eu-doped Y 2 O 3 particles were deposited on the glass plate coated with indium tin oxide through the electrophoretic method. With these glass plates, low-voltage cathodoluminescence (CL) was measured. The nanoparticles synthesized in reverse microemulsion showed a stronger CL intensity and less current saturation than particles formed by bulk precipitation. These CL properties of particles formed in microemulsion might be attributed to the smaller particle size, the larger luminescent surface area, and more well-developed crystalline structure of phosphor than those formed by bulk precipitation.