DataSheet_1_The deformation of marine snow enables its disaggregation in simulated oceanic shear.pdf

Understanding the effect of hydrodynamics on aggregate size and structure is key to predicting mass transport in the aquatic environment. Aggregation theory of particles is well established but our knowledge of deformation processes, biological bonding forces, and their effects on fragmentation of aquatic aggregates is still limited. To better comprehend fragmentation processes and adhesion forces we implemented breakup experiments with diatom and microplastic aggregates made in the laboratory. We captured a substantial number of events showing deformation and subsequent fragmentation of these aggregates in an oscillatory shear flow. Polystyrene and polyethylene aggregates showed distinct fragmentation strengths and provided comparative upper and lower limits to the biological bonding strength of the diatom aggregates. Additionally, we employed a force balance model to evaluate attractive interactions within clusters of particles using the Lagrangian stress history and morphology. We found that the fractal structures of aggregates led to a power law of breakup strength with size and that time-integrated stress governed the overall fragmentation process. We also found that the weakening of the aggregates through deformation with shear exposure enabled their disaggregation at very low shear rates typical of the ocean environment.</p

Video_1_The deformation of marine snow enables its disaggregation in simulated oceanic shear.mp4

Understanding the effect of hydrodynamics on aggregate size and structure is key to predicting mass transport in the aquatic environment. Aggregation theory of particles is well established but our knowledge of deformation processes, biological bonding forces, and their effects on fragmentation of aquatic aggregates is still limited. To better comprehend fragmentation processes and adhesion forces we implemented breakup experiments with diatom and microplastic aggregates made in the laboratory. We captured a substantial number of events showing deformation and subsequent fragmentation of these aggregates in an oscillatory shear flow. Polystyrene and polyethylene aggregates showed distinct fragmentation strengths and provided comparative upper and lower limits to the biological bonding strength of the diatom aggregates. Additionally, we employed a force balance model to evaluate attractive interactions within clusters of particles using the Lagrangian stress history and morphology. We found that the fractal structures of aggregates led to a power law of breakup strength with size and that time-integrated stress governed the overall fragmentation process. We also found that the weakening of the aggregates through deformation with shear exposure enabled their disaggregation at very low shear rates typical of the ocean environment.</p

High Oxygen Barrier Thin Film from Aqueous Polymer/Clay Slurry

A thin film coating with tailorable thickness and clay concentration was prepared by solution casting an aqueous slurry containing poly­(vinyl alcohol) (PVOH) and montmorillonite (MMT) clay. The anisotropic clay platelets have excellent alignment due to self-orientation during drying, which results in good transparency and oxygen barrier. A 50 wt % clay coating, with a thickness around 4 μm and visible light transmission of 58%, improves the oxygen barrier of a 179 μm poly­(ethylene terephthalate) (PET) substrate by more than 3 orders of magnitude. This PVOH/MMT composite thin film also has good thermal stability and mechanical properties. This simple coating procedure could be used for a variety of packaging applications that use plastic film (e.g., food, pharmaceutical, and electronics)

Combined High Stretchability and Gas Barrier in Hydrogen-Bonded Multilayer Nanobrick Wall Thin Films

Hydrogen-bonded multilayer thin films are very stretchable, but their gas barrier properties are modest compared to more traditional ionically bonded assemblies. In an effort to improve the gas barrier of poly­(ethylene oxide) (PEO)–poly­(acrylic acid) (PAA) multilayer films without sacrificing stretchability, montmorillonite (MMT) clay platelets were combined with PAA and alternately deposited with PEO. A ten-bilayer PEO/PAA+MMT film (432 nm thick), deposited on a 1 mm PU substrate, resulted in a 54× reduction in oxygen transmission rate after exposure to a 20% strain. This system is the best combination of stretchability and gas barrier ever reported

Additional file 1 of Kruppel-like factor 13 acts as a tumor suppressor in thyroid carcinoma by downregulating IFIT1

Additional file 1. Supplementary figures

Nanomechanical Behavior of High Gas Barrier Multilayer Thin Films

Nanoindentation and nanoscratch experiments were performed on thin multilayer films manufactured using the layer-by-layer (LbL) assembly technique. These films are known to exhibit high gas barrier, but little is known about their durability, which is an important feature for various packaging applications (e.g., food and electronics). Films were prepared from bilayer and quadlayer sequences, with varying thickness and composition. In an effort to evaluate multilayer thin film surface and mechanical properties, and their resistance to failure and wear, a comprehensive range of experiments were conducted: low and high load indentation, low and high load scratch. Some of the thin films were found to have exceptional mechanical behavior and exhibit excellent scratch resistance. Specifically, nanobrick wall structures, comprising montmorillonite (MMT) clay and polyethylenimine (PEI) bilayers, are the most durable coatings. PEI/MMT films exhibit high hardness, large elastic modulus, high elastic recovery, low friction, low scratch depth, and a smooth surface. When combined with the low oxygen permeability and high optical transmission of these thin films, these excellent mechanical properties make them good candidates for hard coating surface-sensitive substrates, where polymers are required to sustain long-term surface aesthetics and quality

Influence of Graphene Reduction and Polymer Cross-Linking on Improving the Interfacial Properties of Multilayer Thin Films

Graphene is a versatile composite reinforcement candidate due to its strong mechanical, tunable electrical and optical properties, and chemical stability. However, one drawback is the weak interfacial bonding, which results in weak adhesion to substrates. This could be overcome by adding polymer layers to have stronger adherence to the substrate and between graphene sheets. These multilayer thin films were found to have lower resistance to lateral scratch forces when compared to other reinforcements such as polymer/clay nanocomposites. Two additional processing steps are suggested to improve the scratch resistance of these films: graphene reduction and polymer cross-linking. Graphene<b>/</b>polymer nanocomposites consisting of polyvinylamine (PVAm) and graphene oxide (GO) were fabricated using the layer-by-layer assembly (LbL) technique. The reduced elastic modulus and hardness of PVAm/GO films were measured using nanoindentation. Reducing GO enhances mechanical properties by 60–70% while polymer cross-linking maintains this enhancement. Both graphene reduction and polymer cross-linking show significant improvement to scratch resistance. Particularly, polymer cross-linking leads to films with higher elastic recovery, 50% lower adhesive and plowing friction coefficient, 140 and 50% higher adhesive and shear strength values, respectively, and lower material pileup and scratch width/depth

High Thermoelectric Power Factor Organic Thin Films through Combination of Nanotube Multilayer Assembly and Electrochemical Polymerization

In an effort to produce effective thermoelectric nanocomposites with multiwalled carbon nanotubes (MWCNT), layer-by-layer assembly was combined with electrochemical polymerization to create synergy that would produce a high power factor. Nanolayers of MWCNT stabilized with poly­(diallyldimethylammonium chloride) or sodium deoxycholate were alternately deposited from water. Poly­(3,4-ethylene dioxythiophene) [PEDOT] was then synthesized electrochemically by using this MWCNT-based multilayer thin film as the working electrode. Microscopic images show a homogeneous distribution of PEDOT around the MWCNT. The electrical resistance, conductivity (σ) and Seebeck coefficient (<i>S</i>) were measured before and after the PEDOT polymerization. A 30 bilayer MWCNT film (<1 μm thick) infused with PEDOT is shown to achieve a power factor (PF = <i>S</i>²σ) of 155 μW/m K², which is the highest value ever reported for a completely organic MWCNT-based material and competitive with lead telluride at room temperature. The ability of this MWCNT-PEDOT film to generate power was demonstrated with a cylindrical thermoelectric generator that produced 5.5 μW with a 30 K temperature differential. This unique nanocomposite, prepared from water with relatively inexpensive ingredients, should open up new opportunities to recycle waste heat in portable/wearable electronics and other applications where low weight and mechanical flexibility are needed

Odds ratios and 95% CIs for absence due to mental disease or non-mental disease according to proposed cutoff score for relative presenteeism (≤0.8) in actual prospective cohort data.

a<p>Subjects with absence due to mental disease across a 2-year follow up; ^bSubjects with absence due to non-mental disease across a 2-year follow up: OR: odds ratio; CI: confidence interval; *P<0.05; adjusted ORs and 95% CIs were based on multiple logistic regression analysis. The first model was adjusted for age and gender, a second model was further adjusted for depressive symptoms (K6≥13) at baseline, and a third model was further adjusted for drinking habits (drink approximately every day or not), smoking habits (current smoker or not), education level (years), job position (managerial job or not), equivalent income (10,000 yen/year), and exercise in spare time (yes or no) at baseline.</p><p>Odds ratios and 95% CIs for absence due to mental disease or non-mental disease according to proposed cutoff score for relative presenteeism (≤0.8) in actual prospective cohort data.</p

Sensitivity, specificity, and AUC of cutoff value of absolute and relative presenteeism in the prediction of absence due to mental disease.

<p>AUC: the area under the curve; 95% CI: 95% confidence interval;</p><p>Sensitivity, specificity, and AUC of cutoff value of absolute and relative presenteeism in the prediction of absence due to mental disease.</p