Reinforcement of the Political Self Through Selective Exposure to Political Messages

The idea that recipients prefer messages that reinforce preexisting attitudes and self‐perceptions has pervaded much communication research, but effects of selective exposure are rarely examined. This 2‐session experiment (n = 157) investigates such effects. The first session presented computerized questions on 12 political issue attitudes and political self‐concept. Accessibility data were collected based on response times. In the second session, participants browsed through an online magazine including 4 of the 12 issues, each issue being covered by 2 articles featuring opposing viewpoints. Selective exposure was logged and categorized as attitude‐consistent or counterattitudinal. Finally, a questionnaire repeated measures for attitudes and self‐concept. The results show that participants preferred attitude‐consistent over counterattitudinal messages, which strengthened the political self‐concept through increased accessibility.     

Please Your Self: Social Identity Effects on Selective Exposure to News About In‐ and Out‐Groups

Hypotheses were tested in a secondary data analysis of an experiment on selective exposure to positive and negative news articles about same‐ and differently aged individuals. A sample of 178 young (18–30 years) and 98 older adults (50–65 years) browsed an online news magazine while reading times were logged by software. Younger individuals (high status, high uncertainty) generally focused their reading on same‐aged individuals, with a preference on positive news about this in‐group. Older recipients (low‐status, low uncertainty) were more likely to select negative news about young individuals than positive news about this out‐group and negative news about older individuals. Furthermore, exposure to negative news about younger individuals bolstered older recipients' self‐esteem.     

Site‐Selective Self‐Assembly of Colloidal Photonic Crystals

A scalable method for site‐selective, directed self‐assembly of colloidal opals on topologically patterned substrates is presented. Here, such substrate contains optical waveguides which couple to the colloidal crystal. The site‐selectivity is achieved by a capillary network, whereas the self‐assembly process is based on controlled solvent evaporation. In the deposition process, a suspension of colloidal microspheres is dispensed on the substrate and driven into the desired crystallization sites by capillary flow. The method has been applied to realize colloidal crystals from monodisperse dielectric spheres with diameters ranging from 290 to 890 nm. The method can be implemented in an industrial wafer‐scale process.     

Oil‐Based Self‐Healing Barrier Coatings: To Flow and Not to Flow

Localized corrosion involves the selective attack of a metal at a small, exposed site. This can be particularly devastating for load‐bearing structures, which can fail catastrophically even with very little material loss. Unfortunately, local corrosion is difficult to prevent, predict, and detect. Corrosion can be prevented by barrier coatings, however, imperfections such as pinholes and scratches, can expose small areas of metal and eventually lead to localized corrosion. Herein, a new strategy for self‐healing, damage‐tolerant coatings that can mitigate localized corrosion is presented. The new self‐healing system consists of microcapsule‐thickened low‐viscosity oil and exhibits length scale‐dependent viscosity. Macroscopically, the coating is viscous due to the formation of a 3D particle network, which allows it to stick to vertical metal surfaces against gravity and turbulent flow. Microscopically, the oil exhibits low viscosity and can rapidly flow to damaged areas to re‐establish the particle network. The coating exhibits remarkable barrier properties and protects metal from corrosion for a long time. Moreover, the coating is able to repeatedly self‐heal over the same area hundreds of times over. The strategy described here illustrates how contradicting material properties (e.g., viscosity) co‐exist in a “smart” material system by accommodating them at different length scales.     

Self‐Assembly of Selective Interfaces in Organic Photovoltaics

The composition of polymer‐fullerene blends is a critical parameter for achieving high efficiencies in bulk‐heterojunction (BHJ) organic photovoltaics. Achieving the “right” materials distribution is crucial for device optimization as it greatly influences charge‐carrier mobility. The effect of the vertical concentration profile of materials in spin‐coated BHJs on device properties has stirred particularly vigorous debate. Despite available literature on this subject, the results are often contradictory and inconsistent, likely due to differences in sample preparation and experimental considerations. To reconcile published results, the influence of heating, surface energy, and solvent additives on vertical segregation and doping in polymer‐fullerene BHJ organic photovoltaics are studied using neutron reflectometry and near edge X‐ray absorption fine structure spectroscopy. It is shown that surface energies and solvent additives greatly impact heat‐induced vertical segregation. Interface charging due to Fermi level mismatch increases (6,6)‐phenyl‐C₆₁‐butyric acid methyl ester (PCBM)‐enrichment at the BHJ/cathode interface. Current–voltage measurements show that self‐assembly of interfaces affects the open‐circuit voltage, resulting in clear changes to the power conversion efficiency.     

The Gender News Use Divide: Americans' Sex-Typed Selective Exposure to Online News Topics

To examine psychological origins of sex-typed news preferences, an online newsmagazine was presented to 196 American participants in an experimental setting. The presented articles featured the same portions of social/interpersonal and achievement/performance topics. Newsreaders' selective news exposure was unobtrusively logged. Results show that, in line with gender stereotypes, women favor social/interpersonal topics and men prefer achievement/performance issues. Newsreaders' affiliation motive, self-esteem, and, to a small extent, gender schemata influenced what news content was preferred.     

Bacterium‐Templated Polymer for Self‐Selective Ablation of Multidrug‐Resistant Bacteria

The recognition and inactivation of specific pathogenic bacteria remain an enormous scientific challenge and an important therapeutic goal. Therefore, materials that can selectively target and kill specific pathogenic bacteria, without harming beneficial strains are highly desirable. Here, a material platform is reported that exploits bacteria as a template to synthesize polymers with aggregation‐induced emission (AIE) characteristic by copper‐catalyzed atom transfer radical polymerization for self‐selective killing of the bacteria that templates them with no antimicrobial resistance. The bacteria‐templated polymers show very weak fluorescence in aqueous media, however, the fluorescence is turned on upon recognition of the bacteria used as the template to synthesize the polymer even at a low concentration of 600 ng mL^?1. Moreover, the incorporated AIE fluorogens (AIEgens) can act as an efficient photosensitizer for reactive oxygen species (ROS) generation after bacteria surface binding, which endows the templated polymers with the capability for selective bacterial killing. The bacterium‐templated synthesis is generally applicable to a wide range of bacteria, including clinically isolated multidrug‐resistant bacterial strains. It is envisioned that the bacterium‐templated method provides a new strategy for bacteria‐specific diagnostic and therapeutic applications.     

Tunable Band‐Selective UV‐Photodetectors by 3D Self‐Assembly of Heterogeneous Nanoparticle Networks

Accurate detection of ultraviolet radiation is critical to many technologies including wearable devices for skin cancer prevention, optical communication systems, and missile launch detection. Here, a nanoscale architecture is presented for band‐selective UV‐photodetectors, which features unique tunability and miniaturization potential. The device layout relies on the 3D integration of ultraporous layers of tailored nanoparticles. By tailoring the transmittance window between the indirect band gap of TiO₂ nanoparticles and the sharp edge of the direct band gap of ZnO, a band‐selective photoresponse is achieved with tunable bandwidth to less than 30 nm and photo‐ to dark‐current ratios of several millions at a light intensity of 86 μW cm^?2 and operation bias of 1 V. The potential of this integrated morphology is shown by fabrication of the first inherent UVA photodetector with selectivity against the edge of the UVB and visible light of nearly 60 times. This tunable architecture and nanofabrication approach are compatible with state‐of‐the micromachining technologies and provide a flexible solution for the engineering of wearable band‐selective photodetectors.     

Hydroactuated Configuration Alteration of Fibrous Dandelion Pappi: Toward Self‐Controllable Transport Behavior

Stimuli‐responsive materials, especially those inspired by natural organism, have been extensively studied because of their versatile applications. Here, this study demonstrates that the unique hydroactuated reversible configuration alternation of the dandelion pappus, featured by the responsive spatial closing and opening the umbrella‐like pappus depending on the environmental humidity, is a determining factor that allows the pappus to regulate its transport behavior. It is proposed that the anisotropic hydroactuated swelling of tracheids, which are typically arranged with an oblique crossing orientation, helps to generate the directional stress on the pappus. By this strategy, the pappus control its transport behavior in response to the environmental moisture, which allows long‐distance and effective seeds dispersal selectively to local sites for optimal reproduction. Inspired by this, this study develops a hydroresponsive fiber array by integrating the hydrogel, whose configuration can be altered reversibly between the opening and closing state depending on the environmental humidity. This study believes the research can offer inspirations for designing and developing adaptive devices by using fibers array, as smart aerocraft.     

Growth of Single‐Crystalline Wurtzite Aluminum Nitride Nanotips with a Self‐Selective Apex Angle

Single‐crystalline, hexagonal aluminum nitride nanotips are fabricated using a vapor‐transport and condensation process (VTCP) on silicon substrates with or without a catalyst layer. The resultant tips have very sharp nanoscale apexes (～1 nm), while their bases and lengths are up to hundreds of nanometers wide and several micrometers long, respectively. It has been demonstrated that the thickness of the gold‐catalyst layer plays a critical role in controlling the size of the tip; in addition, a catalyst‐free growth mode has been observed, which results in lesser control over the nanotip morphology. Nevertheless, a remarkably narrow distribution of the apex angle of the nanotips, regardless of whether or not a catalyst was used in the VTCP, has been obtained. Compared with the commonly observed ridge and pyramid structures, the nanotips produced by VTCP have higher angles (～81°) between the tilted (221) and the basal (001) planes that encase it. A mechanism for this self‐selective apex angle in aluminum nitride nanotip growth is proposed.     

Temperature‐Induced Hydrogels Through Self‐Assembly of Cholesterol‐Substituted Star PEG‐b‐PLLA Copolymers: An Injectable Scaffold for Tissue Engineering

Partially cholesterol‐substituted 8‐arm poly(ethylene glycol)‐block‐poly(L ‐lactide) (8‐arm PEG‐b‐PLLA‐cholesterol) has been prepared as a novel star‐shaped, biodegradable copolymer derivative. The amphiphilic 8‐arm PEG‐b‐PLLA‐cholesterol aqueous solution (polymer concentration, above 3 wt%) exhibits instantaneous temperature‐induced gelation at 34 °C, but the virgin 8‐arm PEG‐b‐PLLA does not, irrespective of concentration. Moreover, an extracellular matrix (ECM)‐like micrometer‐scale network structure has been created with favorable porosity for three‐dimensional proliferation of cells inside the hydrogel. This network structure is mainly attributed to specific self‐assembly between cholesterol groups. The 10 and 20 wt% hydrogels are eroded gradually in phosphate buffered saline at 37 °C over the course of a month, and after that the gel becomes completely dissociated. Moreover, L929 cells encapsulated into the hydrogel are viable and proliferate three‐dimensionally inside the hydrogels. Thus, in‐vitro cell culture studies demonstrate that 8‐arm PEG‐b‐PLLA‐cholesterol is a promising candidate as a novel injectable cellular scaffold.     

Selective Formation of Bi‐Component Arrays Through H‐Bonding of Multivalent Molecular Modules

Here, the formation of discrete supramolecular mono‐ and bi‐component architectures from novel and multivalent molecular modules bearing complementary recognition moieties that are prone to undergo multiple H‐bonds, such as 2,6‐di(acetylamino)pyridine and uracil residues, is described. These nanostructured H‐bonded arrays, including dimeric and pentameric species, are thoroughly characterized in solution by NMR, in the solid state by FT‐IR, and at the solid–liquid interface by means of scanning tunneling microscopy. The employed strategy is extremely versatile as it relies on the tuning of the valency, size, and geometry of the molecular modules; thus, it may be of interest for the bottom‐up fabrication of nanostructured functional materials with sub‐nanometer precision.     

Universal Control on Pyroresistive Behavior of Flexible Self‐Regulating Heating Devices

Smart heating devices with reliable self‐regulating performances and high efficiency, combined with additional properties like mechanical flexibility, are of particular interest in healthcare, soft robotics, and smart buildings. Unfortunately, the development of smart heaters necessitates managing normally conflicting requirements such as good self‐regulating capabilities and efficient Joule heating performances. Here, a simple and universal materials design strategy based on a series connection of different conductive polymer composites (CPC) is shown to provide unique control over the pyroresistive properties. Hooke's and Kirchhoff's laws of electrical circuits can simply predict the overall pyroresistive behavior of devices connected in series and/or parallel configurations, hence providing design guidelines. An efficient and mechanically flexible Joule heating device is hence designed and created. The heater is characterized by a zero temperature coefficient of resistance below the self‐regulating temperature, immediately followed by a large and sharp positive temperature coefficient (PTC) behavior with a PTC intensity of around 10⁶. Flexibility and toughness is provided by the selected elastomeric thermoplastic polyurethane (TPU) matrix as well as the device design. The universality of the approach is demonstrated by using different polymer matrices and conductive fillers for which repeatable results are consistently obtained.     

Self‐Assembled Nanoparticles with Dual Effects of Passive Tumor Targeting and Cancer‐Selective Anticancer Effects

Nanoparticular drug delivery systems may help to overcome the limitations of conventional chemotherapy. They have been reported to improve the specificity of distribution, the bioavailability, and the solubility of drugs, as well as the duration of drug efficacy, and helping to overcome multidrug resistance. Although various polymeric nanoparticles have been developed for delivery of anticancer agents, most nanoparticles still focus on solubilizing drugs, improving targeting ability, and reducing side effects. In particular, targeting to the tumor is typically improved through passive or active targeting. Despite great achievements in both strategies, yet to be resolved are issues of toxicity in normal cells and enhancement of tumor‐specificity. A new approach combining the dual strategies of passive tumor targeting and cancer‐selective efficacy is proposed. Recombinant human gelatin conjugated with lipoic acid (rHG‐LA) developed in this study forms nanoparticles spontaneously in aqueous solution and encapsulates alpha‐tocopheryl succinate (α‐TOS), a well‐known cancer‐selective apoptosis‐inducing agent, within a hydrophobic core during the self‐assembly. This study describes the promising applicability of α‐TOS‐loaded rHG‐LA nanoparticles with passive targeting ability and cancer‐specificity.     

Voices of Hunger: Addressing Health Disparities Through the Culture‐Centered Approach

Hunger is a key marker of health disparity, depicting the everyday consequences of inequalities that are physiologically felt directly by the most vulnerable segments of the population, often resulting from the broader structural inequities in a society. In this project, we report our work with food insecurity in West Bengal, India and Indiana, USA. Through interviews, focus groups, community‐wide discussions, photo exhibits cocreated through the PhotoVoice method, and community meetings, community members develop solutions that are meaningful to their everyday lived experiences. White Papers, policy briefs, exhibits, community meetings, and coalitions emerge as solutions developed through our partnerships that focus on addressing specific problems related to food insecurity by fostering spaces for listening to the voices of the food insecure.     

Self‐Healing Silk Fibroin‐Based Hydrogel for Bone Regeneration: Dynamic Metal‐Ligand Self‐Assembly Approach

Despite advances in the development of silk fibroin (SF)‐based hydrogels, current methods for SF gelation show significant limitations such as lack of reversible crosslinking, use of nonphysiological conditions, and difficulties in controlling gelation time. In the present study, a strategy based on dynamic metal‐ligand coordination chemistry is developed to assemble SF‐based hydrogel under physiological conditions between SF microfibers (mSF) and a polysaccharide binder. The presented SF‐based hydrogel exhibits shear‐thinning and autonomous self‐healing properties, thereby enabling the filling of irregularly shaped tissue defects without gel fragmentation. A biomineralization approach is used to generate calcium phosphate‐coated mSF, which is chelated by bisphosphonate ligands of the binder to form reversible crosslinkages. Robust dually crosslinked (DC) hydrogel is obtained through photopolymerization of acrylamide groups of the binder. DC SF‐based hydrogel supports stem cell proliferation in vitro and accelerates bone regeneration in cranial critical size defects without any additional morphogenes delivered. The developed self‐healing and photopolymerizable SF‐based hydrogel possesses significant potential for bone regeneration application with the advantages of injectability and fit‐to‐shape molding.     

pH‐Based Regulation of Hydrogel Mechanical Properties Through Mussel‐Inspired Chemistry and Processing

The mechanical holdfast of the mussel, the byssus, is processed at acidic pH yet functions at alkaline pH. Byssi are enriched in Fe³⁺ and catechol‐containing proteins, species with chemical interactions that vary widely over the pH range of byssal processing. Currently, the link between pH, Fe³⁺‐catechol reactions, and mechanical function is poorly understood. Herein, it is described how pH influences the mechanical performance of materials formed by reacting synthetic catechol polymers with Fe³⁺. Processing Fe³⁺‐catechol polymer materials through a mussel‐mimetic acidic‐to‐alkaline pH change leads to mechanically tough materials based on a covalent network fortified by sacrificial Fe³⁺‐catechol coordination bonds. These findings offer the first direct evidence of Fe³⁺‐induced covalent cross‐linking of catechol polymers, reveal additional insight into the pH dependence and mechanical role of Fe³⁺‐catechol interactions in mussel byssi, and illustrate the wide range of physical properties accessible in synthetic materials through mimicry of mussel‐protein chemistry and processing.     

Understanding and Controlling the Self‐Folding Behavior of Poly (N‐Isopropylacrylamide) Microgel‐Based Devices

Poly(N‐isopropylacrylamide) (pNIPAm) microgel‐based materials can be fabricated that self‐fold into three‐dimensional structures in response to changes in the environmental humidity. The materials are composed of a semi‐rigid polymer substrate coated with a thin layer of Au; the Au layer is subsequently coated with a pNIPAm‐based microgel layer and finally covered with a solution of polydiallyldimethylammonium chloride (pDADMAC). The pDADMAC layer contracts upon drying causing the material to deform (typically bending); this deformation is completely reversible over many cycles as the environmental humidity is systematically varied. Here, by varying the size and aspect ratio of the polymer substrate, it is possible to develop a set of empirical rules that can be applied to predict the material's self‐folding behavior. From these rules, materials that self‐fold from two‐dimensional, flat objects into discrete three‐dimensional structures, which are fully capable of unfolding and folding multiple times in response to humidity, are designed.