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Abstract Biofilm formation is a major cause of hospital‐acquired infections. Research into biofilm‐resistant materials is therefore critical to reduce the frequency of these events. Polymer microarrays offer a high‐throughput approach to enable the efficient discovery of novel biofilm‐resistant polymers. Herein, bacterial attachment and surface chemistry are studied for a polymer microarray to improve the understanding ofPseudomonas aeruginosabiofilm formation on a diverse set of polymeric surfaces. The relationships between time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) data and biofilm formation are analyzed using linear multivariate analysis (partial least squares [PLS] regression) and a nonlinear self‐organizing map (SOM). The SOM models revealed several combinations of fragment ions that are positively or negatively associated with bacterial biofilm formation, which are not identified by PLS. With these insights, a second PLS model is calculated, in which interactions between key fragments (identified by the SOM) are explicitly considered. Inclusion of these terms improved the PLS model performance and shows that, without such terms, certain key fragment ions correlated with bacterial attachment may not be identified. The chemical insights provided by the combination of PLS regression and SOM will be useful for the design of materials that support negligible pathogen attachment. 

Abstract Polymer‐derived amorphous SiCN has excellent high‐temperature stability and properties. To reduce the shrinkage during pyrolysis and to improve the high‐temperature oxidation resistance, Y₂O₃was added as a filler. In this study, polymer‐derived SiCN–Y₂O₃composites were fabricated by mixing a polymeric precursor of SiCN with Y₂O₃submicron powders in different ratios. The mixtures were cross‐linked and pyrolyzed in argon. SiCN–Y₂O₃composites were processed using field‐assisted sintering technology at 1350°C for 5 min under vacuum. Dense SiCN–Y₂O₃composite pellets were successfully made with relative density higher than 98% and homogeneous microstructure. Due to low temperature and short time of the heat‐treatment, the grain growth of Y₂O₃was substantially inhibited. The Y₂O₃grain size was ∼1 μm after sintering. The composites’ heat capacity, thermal diffusivity, and thermal expansion coefficients were characterized as a function of temperature. The thermal conductivity of the composites ceramics decreased as the amount of amorphous SiCN increased and the coefficient of thermal expansion (CTE) of the composites increased with Y₂O₃content. However, the thermal conductivity and CTE did not follow the rule of mixture. This is likely due to the partial oxidation of SiCN and the resultant impurity phases such as Y₂SiO₅, Y₂Si₂O₇, and Y_4.67(SiO₄)₃O. 

Abstract In this study, we demonstrate a novel environmental barrier coating processed from polymer‐derived ceramics (PDCs) with homogeneously distributed sub‐micrometer Y₂O₃as the filler. Under suitable conditions, dense and crack‐free coatings can be achieved for all the designed compositions with the volumetric content of Y₂O₃varied from 45 to 93 vol%. To process the PDC SiC–Y₂O₃composite coatings, Y₂O₃particles and SiC liquid precursor were uniformly dispersed in hexane and then dip‐coated on SiC substrates. After cross‐linking at 250°C and heat‐treated at 900°C in argon, dense and crack‐free PDC SiC–Y₂O₃composite coatings were formed. The effect of coating thickness and heat‐treatment temperature on the formation of cracks due to constrained pyrolysis was studied. The critical thickness for realizing crack‐free coatings of three compositions (i.e., 93, 77, and 45 vol% Y₂O₃) was studied for heat treatment from 1000 to 1300°C using atomic force microscope and scanning electron microscopy. As heat‐treatment temperature increases, the critical coating thickness decreases for the same coating compositions due to enhanced shrinkage at higher temperature. With higher Y₂O₃content, the critical thickness of the coating increased. The inert Y₂O₃particles reduce the amount of polymer leading to reduction in the overall constrained shrinkage of the coating during heat treatment. 

Electrochemical‐based memristors are highly attractive that are capable of nonvolatile analog tuning, long‐term state stability, low power consumption, device scalability, and fast switching speeds. Through the combination of film deposition techniques, i.e., vapor phase polymerization and screen printing, fabrication of a poly(4‐(6‐hexyl)‐4H‐dithieno[3,2‐b:2′,3′‐d]pyrrole) (p6DTP)‐based synaptic‐emulating three‐terminal memristor is designed. Through voltage‐driven pulse programming, and square waves with an amplitude of 100 mV and duration of 100 msec, the device exhibits a power consumption of 1 pJmm⁻²per synaptic event. By analyzing the fundamental operational trends of the p6DTP‐based device, simple and advanced integrated applications can be demonstrated along with synaptic‐like responses. This effort is the first presentation of the vapor phase polymerization technique for any dithienopyrrole‐based monomers, along with the physical implementation of any memristive system as an advanced logical circuit, demonstrated here as a cascaded combinational logic gate. 

The present review outlines a comprehensive overview of the research on silicon oxycarbide (SiOC) materials, which are synthesized by various synthetic routes and are investigated as alternatives to crystalline silicon anodes. 

Autofluorescence (AF) poses challenges for detecting proteins of interest in situ when employing immunofluorescence (IF) microscopy. This interference is particularly pronounced in strongly autofluorescent tissues such as myocardium, where tissue AF can be comparable to IF. Although various histochemical methods have been developed to achieve effective AF suppression in different types of tissue, their applications on myocardial  samples have not been well validated. Due to inconsistency across different autofluorescent structures in sometypes of tissue, it is unclear if these methods can effectively suppress AF across all autofluorescent structures within the myocardium. Here, we quantitatively evaluated the performance of several commonly used quenching treatments on formaldehyde-fixed myocardial samples, including 0.3 M glycine, 0.3% Sudan Black B (SBB), 0.1% and 1% sodium borohydride (NaBH4), TrueVIEW® and TrueBlack®. We further assessed their quenching performance by employing the pre-treatment and post-treatment protocols, designed to cover two common IF staining scenarios where buffers contained detergents or not. The results suggest that SBB and TrueBlack® outperform other reagents in AF suppression on formaldehyde-fixed myocardial samples in both protocols. Furthermore, we inspected the quenching performance of SBB and TrueBlack® on major autofluorescent myocardial structures and evaluated their influence on IF imaging. The results suggest that SBB outperforms TrueBlack® in quenching major autofluorescent structures, while TrueBlack® excels in preserving IF labeling signal. Surprisingly, we found the treatment of NaBH4 increased AF signal and enhanced the AF contrast of major autofluorescent structures. This finding suggests that NaBH4 has the potential to act as an AF enhancer and may facilitate the interpretation of myocardial structures without the need for counterstaining.