5 nm Silver Nanoparticles Amplify Clinical Features of Atopic Dermatitis in Mice by Activating Mast Cells

The triggering effect of silver nanoparticles (NPs) on the induction of allergic reactions is evaluated, by studying the activation of mast cells and the clinical features of atopic dermatitis in a mouse model. Granule release is induced in RBL‐2H3 mast cells by 5 nm, but not 100 nm silver NPs. Increases in the levels of reactive oxygen species (hydrogen peroxide and mitochondrial superoxide) and intracellular Ca⁺⁺ in mast cells are induced by 5 nm silver NPs. In a mouse model of atopic dermatitis induced by a mite allergen, the skin lesions are more severe and appear earlier in mice treated simultaneously with 5 nm silver NPs and allergen compared with mice treated with allergen alone or 100 nm silver NPs and allergen. The histological findings reveal that number of tryptase‐positive mast cells and total IgE levels in the serum increase in mice treated with 5 nm silver NPs and allergen. The results in this study indicate that cotreatment with 5 nm silver NPs stimulates mast cell degranulation and induces earlier and more severe clinical alterations in allergy‐prone individuals.     

Textile‐surface interfacial asymmetric polymerization

This research demonstrated that polymerization of aniline on cellulose produces chiroptically active composites. Polymerization of aniline in the presence of cotton fibers consisting of chiral cellulose are performed to prepare a polyaniline (PANI)/cotton composite. The polymerization is conducted at the cotton interface. The resultant PANI/cotton composite shows chiroptical activity elucidated with diffuse reflectance circular dichroism. In this reaction, textile‐surface interfacial asymmetric polymerization is performed with imprinting of chiral structure from the cotton as a natural chiroptically active polymer to the PANI. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41118.     

Thermally Controlled,Patterned Graphene Transfer Printing for Transparent and Wearable Electronic/Optoelectronic System

Graphene has been highlighted as a platform material in transparent electronics and optoelectronics, including flexible and stretchable ones, due to its unique properties such as optical transparency, mechanical softness, ultrathin thickness, and high carrier mobility. Despite huge research efforts for graphene‐based electronic/optoelectronic devices, there are remaining challenges in terms of their seamless integration, such as the high‐quality contact formation, precise alignment of micrometer‐scale patterns, and control of interfacial‐adhesion/local‐resistance. Here, a thermally controlled transfer printing technique that allows multiple patterned‐graphene transfers at desired locations is presented. Using the thermal‐expansion mismatch between the viscoelastic sacrificial layer and the elastic stamp, a “heating and cooling” process precisely positions patterned graphene layers on various substrates, including graphene prepatterns, hydrophilic surfaces, and superhydrophobic surfaces, with high transfer yields. A detailed theoretical analysis of underlying physics/mechanics of this approach is also described. The proposed transfer printing successfully integrates graphene‐based stretchable sensors, actuators, light‐emitting diodes, and other electronics in one platform, paving the way toward transparent and wearable multifunctional electronic systems.     

Effects of rapid thermal process on the junction properties of aluminum rear emitter solar cells

N-type silicon with aluminum emitters for rear junctions was studied; aluminum back surface fields were replaced with n-type silicon wafers. Aluminum rear emitters for n-type silicon solar cells were studied with various rapid thermal processing conditions. With fast ramping-up and fast cooling, an aluminum rear junction was formed uniformly with low emitter recombination current. The effects of junction quality on solar cell efficiency were investigated.     

Superfluidity in Hydrogen-Deuterium Mixed Clusters

Path-integral Monte Carlo calculations have been performed on para-H₂ clusters mixed with several ortho-D₂ molecules, (D₂) $_{N_{D}}$ (H₂) $_{N_{H}}$ with 1≤N _D ≤5 and 10≤N _H ≤20, to study their superfluid behavior at low temperatures. It is found that heavier D₂ molecules are located near the center of the mixed cluster, and radial density distributions of D₂ and H₂ tend to separate from each other as the number of D₂ molecules increases. We have also found significant suppression of superfluidity at specific cluster sizes when compared to those of the neighboring sizes. This can be understood in terms of the magic number stability previously reported in hydrogen clusters. Finally we present the local superfluid density distributions in the mixed clusters, which shows uniform local superfluidity of H₂ except near D₂ molecules.     

Modeling L2 Writer Voice: Discoursal Positioning in Fanfiction Writing

Of various online discourses, distinctive design features of fanfiction discourse have given rise to a new social space that holds great potential for the negotiation of identity. In this study, I propose that fanfiction discourse creates a social space that helps shape the voice construction of the L2 writer. In order to understand how the L2 writer's multiple social positions within fanfiction discourse affect voice construction, I analyze a popular online culture-based writing website, <www.fanfiction.net>. Three dominant design features are identified that allow various forms of participation and levels of engagement by its members: intertextuality, dialogic interaction, and electronic text. These three features are actualized in three different positionings (ideational, interpersonal, and textual) that Ivani? and Camps (2001) believe writers take on when constructing a voice. Results suggest that the two L2 participants in my study created voices in multiple positionings made available by re-purposing a pop-culture storyline or characters, communication with audiences, and digital resources. Overall, this study offers a nuanced view of how voice is projected and negotiated within the intersections of multiple online discourses and how it relates to L2 writing in the digital era.     

Effects of backpack weight on the performance of basic short-term/working memory tasks during flat-surface standing

This study empirically investigated the effects of backpack weight on the performance of three basic short-term/working memory (STM/WM) tasks during flat-surface standing. Four levels of backpack weight were considered: 0, 15, 25 and 40% of the body weight. The three STM/WM tasks were the Corsi block, digit span and 3-back tasks, corresponding to the visuo-spatial sketchpad, phonological loop and central executive of WM, respectively. Thirty participants conducted the STM/WM tasks while standing with loaded backpack. Major study findings were that (1) increased backpack weight adversely affected the scores of all three STM/WM tasks; and, (2) the adverse effect of backpack weight was less pronounced for the phonological loop STM task than the other STM/WM tasks. The study findings may help understand and predict the impacts of body-worn equipment weight on the worker’s mental task performance for various work activities requiring simultaneous performance of mental and physical tasks.

Practitioner summary: The current study empirically examined the effects of backpack weight on the performance of three basic STM/WM tasks. The study findings entail that reduces the weight of body-worn equipment can positively impact the worker’s mental task performance in addition to reducing the worker's bodily stresses.

Abbreviations: ACC: anterior cingulate cortex; AP: anterior-posterior; BW: body weight; CoP: centre of pressure; C-S: central executive working memory task and standing; DLPFC: dorsolateral prefrontal cortex; HIP: human information processing; ML: medio-lateral; PMC: premotor cortex; P-S: phonological loop short-term memory task and standing; SMA: supplementary motor area; STM: short-term memory; VLPFC: ventrolateral prefrontal cortex; V-S: visuo-spatial short-term memory task and standing; WM: working memory     

Biocomputing with Nanostructures on Lipid Bilayers

Biocomputation is the algorithmic manipulation of biomolecules. Nanostructures, most notably DNA nanostructures and nanoparticles, become active substrates for biocomputation when modified with stimuli‐responsive, programmable biomolecular ligands. This approach—biocomputing with nanostructures (“nano‐bio computing”)—allows autonomous control of matter and information at the nanoscale; their dynamic assemblies and beneficial properties can be directed without human intervention. Recently, lipid bilayers interfaced with nanostructures have emerged as a new biocomputing platform. This new nano‐bio interface, which exploits lipid bilayers as a chemical circuit board for information processing, offers a unique reaction space for realizing nanostructure‐based computation at a previously unexplored dimension. In this Concept, recent advances in nano‐bio computing are briefly reviewed and the newly emerging concept of biocomputing with nanostructures on lipid bilayers is introduced.     

Biofilm-inactivating activity of silver nanoparticles: A comparison with silver ions

The antimicrobial activity of silver nanoparticles (AgNPs) against Pseudomonas aeruginosa PA01 planktonic and biofilm bacteria was examined; their activity was compared with that of silver ions. The inactivation of biofilms by AgNPs was greatly influenced by stirring, which caused an increased AgNP biosorption. Although the activity of AgNPs against planktonic cells was ca. 10% that of silver ions, their activity against biofilm cells was comparable to the silver ions’ activity at the same concentration after 90 min under stirring (ca. 3.5 log inactivation). AgNPs inactivated biofilms in a biosorption-dependent manner, whereas this was not the case for silver ions.     

Invited review: Microbe-mediated aflatoxin decontamination of dairy products and feeds

Aspergillus flavus, Aspergillus parasiticus, and Aspergillus nomius contaminate corn, sorghum, rice, peanuts, tree nuts, figs, ginger, nutmeg, and milk. They produce aflatoxins, especially aflatoxin B₁, which is classified as a Group 1 carcinogen by the International Agency for Research on Cancer. Many studies have focused on aflatoxin removal from food or feed, especially via microbe-mediated mechanisms—either adsorption or degradation. Of the lactic acid bacteria, Lactobacillus rhamnosus GG efficiently binds aflatoxin B₁, and a peptidoglycan in the bacterium cell wall plays an important role. This ability of L. rhamnosus GG should be applied to the removal of aflatoxin B₁. Aflatoxin can be removed using other aflatoxin-degrading microorganisms, including bacterial and fungal strains. This review explores microbe-associated aflatoxin decontamination, which may be used to produce aflatoxin-free food or feed.