Utilizing Binary Phase Segregation and Extrusion to Enhance the Electronic Properties of Graphene Nanocomposites.

Our goal in this study is to incorporate graphene nanoplatelets (GNPs) in a polymer blend of poly(lactic acid) (PLA) and isotactic polypropylene (iPP) to facilitate the dispersion of GNPs and use the morphology of phase segregation to create a pathway for concentrating GNPs to achieve percolation with lower GNP concentration. Investigating the interfacial properties between PLA/GNPs and iPP/GNPs, we noticed that iPP has a lower contact angle on GNPs compared to PLA on GNPs. This showed a great potential that the GNP are easily confined in iPP rather than in PLA domains or at the PLA/PP interfaces.

Molecular Basis for Surface-Initiated Non-Thrombin-Generated Clot Formation Following Viral Infection.

In this paper, we propose a model that connects two standard inflammatory responses to viral infection, namely, elevation of fibrinogen and the lipid drop shower, to the initiation of non-thrombin-generated clot formation. In order to understand the molecular basis for the formation of non-thrombin-generated clots following viral infection, human epithelial and Madin-Darby Canine Kidney (MDCK, epithelial) cells were infected with H1N1, OC43, and adenovirus, and conditioned media was collected, which was later used to treat human umbilical vein endothelial cells and human lung microvascular endothelial cells. After direct infection or after exposure to conditioned media from infected cells, tissue surfaces of both epithelial and endothelial cells, exposed to 8 mg/mL fibrinogen, were observed to initiate fibrillogenesis in the absence of thrombin.

Autologous Skin Grafts, versus Tissue-engineered Skin Constructs: A Systematic Review and Meta-analysis.

Unlabelled: For over 100 years, autologous skin grafts have remained the gold standard for the reconstruction of wounds but are limited in availability. Acellular tissue-engineered skin constructs (acellular TCs) and cellular tissue-engineered skin constructs (cellular TCs) may address these limitations. This systematic review and meta-analysis compare outcomes between them.

Expression Microdissection for the Analysis of miRNA in a Single-Cell Type.

Cell-specific microRNA (miRNA) expression estimates are important in characterizing the localization of miRNA signaling within tissues. Much of these data are obtained from cultured cells, a process known to significantly alter miRNA expression levels. Thus, our knowledge of in vivo cell miRNA expression estimates is poor.

Real-time emotion detection by quantitative facial motion analysis.

Background: Research into mood and emotion has often depended on slow and subjective self-report, highlighting a need for rapid, accurate, and objective assessment tools.

Methods: To address this gap, we developed a method using digital image speckle correlation (DISC), which tracks subtle changes in facial expressions invisible to the naked eye, to assess emotions in real-time. We presented ten participants with visual stimuli triggering neutral, happy, and sad emotions and quantified their associated facial responses via detailed DISC analysis.

Enhancement of acellular biomineralization, dental pulp stem cell migration, and differentiation by hybrid fibrin gelatin scaffolds.

Objective: The current in vitro study aims to evaluate cross-linked hydrogels with and without the addition of fibrin that could potentially be used in endodontic regeneration as a scaffold material.

Methods: Synthesis of gelatin/fibrin scaffold, and performing nanoscale characterization using cryo-electron microscopy, dynamic rheology, and XRF for structure property relations; plating dental pulp stem cells and determining mineralization, migration, and differentiation using rt-PCR, XRF, and Raman spectroscopy.

Results: Cryo electron imaging shows gelatin and fibrin, when gelled separately to form classical rectangular cross-linked networks, where the modulus scales inversely with the cube root of the mesh size.

Enhancing Crystallization in Hybrid Perovskite Solar Cells Using Thermally Conductive 2D Boron Nitride Nanosheet Additive.

Controlling crystallization and grain growth is crucial for realizing highly efficient hybrid perovskite solar cells (PSCs). In this work, enhanced PSC photovoltaic performance and stability by accelerating perovskite crystallization and grain growth via 2D hexagonal boron nitride (hBN) nanosheet additives incorporated into the active perovskite layer are demonstrated. In situ X-ray scattering and infrared thermal imaging during the perovskite annealing process revealed the highly thermally conductive hBN nanosheets promoted the phase conversion and grain growth in the perovskite layer by facilitating a more rapid and spatially uniform temperature rise within the perovskite film.

Non-cytotoxic Root Canal Dressing with Improved Antimicrobial Efficacy.

Introduction: Recurrent endodontic infections are primarily caused by Enterococcus faecalis and are more challenging to treat, compared with primary infection of the root canal system. Calcium hydroxide (CH) is used as an interappointment dressing in endodontics despite its inefficacy against E. faecalis and other pathogens.

Sustainable Plant-Based Biopolymer Membranes for PEM Fuel Cells.

Carboxycellulose nanofibers (CNFs) promise to be a sustainable and inexpensive alternative material for polymer electrolyte membranes compared to the expensive commercial Nafion membrane. However, its practical applications have been limited by its relatively low performance and reduced mechanical properties under typical operating conditions. In this study, carboxycellulose nanofibers were derived from wood pulp by TEMPO oxidation of the hydroxyl group present on the C6 position of the cellulose chain.

Modeling of the thermal properties of SARS-CoV-2 S-protein.

We calculate the thermal and conformational states of the spike glycoprotein (S-protein) of SARS-CoV-2 at seven temperatures ranging from 3°C to 95°C by all-atom molecular dynamics (MD) µs-scale simulations with the objectives to understand the structural variations on the temperatures and to determine the potential phase transition while trying to correlate such findings of the S-protein with the observed properties of the SARS-CoV2. Our simulations revealed the following thermal properties of the S-protein: 1) It is structurally stable at 3°C, agreeing with observations that the virus stays active for more than two weeks in the cold supply chain; 2) Its structure varies more significantly at temperature values of 60°C-80°C; 3) The sharpest structural variations occur near 60°C, signaling a plausible critical temperature nearby; 4) The maximum deviation of the receptor-binding domain at 37°C, corroborating the anecdotal observations that the virus is most infective at 37°C; 5) The in silico data agree with reported experiments of the SARS-CoV-2 survival times from weeks to seconds by our clustering approach analysis. Our MD simulations at µs scales demonstrated the S-protein's thermodynamics of the critical states at around 60°C, and the stable and denatured states for temperatures below and above this value, respectively.

Potentiometric Biosensors Based on Molecular-Imprinted Self-Assembled Monolayer Films for Rapid Detection of Influenza A Virus and SARS-CoV-2 Spike Protein.

Rapid, yet accurate and sensitive testing has been shown to be critical in the control of spreading pandemic diseases such as COVID-19. Current methods which are highly sensitive and can differentiate different strains are slow and cannot be conveniently applied at the point of care. Rapid tests, meanwhile, require a high titer and are not sufficiently sensitive to discriminate between strains.

Efficacy of hypochlorous acid (HOCl) fog in sanitizing surfaces against Enterococcus faecalis.

Background: Fogging is an efficient method when disinfection of large areas is desired.

Methods: Two methods of ultrasonic fogging, pulsed and continuous, were compared on bacteria dried on either aluminum or polystyrene surfaces. We characterized commercial and home-made hypochlorous acid (HOCl) with respect to storage and means of production.

Novel characteristics of soluble fibrin: hypercoagulability and acceleration of blood sedimentation rate mediated by its generation of erythrocyte-linked fibers.

Soluble fibrin (SF) in blood consists of monomers lacking both fibrinopeptides A with a minor population in multimeric clusters. It is a substantial component of isolated fibrinogen (fg), which spontaneously self-assembles into protofibrils progressing to fibers at sub-physiologic temperatures, a process enhanced by adsorption to hydrophobic and some metal surfaces. Comparisons of SF-rich (FR) and SF-depleted (FD) fg isolates disclosed distinct molecular imprints of each via an adsorption/desorption procedure using gold surfaced silica microplates.

In Vitro Toxicity of Bone Graft Materials to Human Mineralizing Cells.

Bone graft materials from synthetic, bovine, and human sources were analyzed and tested for in vitro cytotoxicity on dental pulp stem cells (DPSCs) and osteosarcoma cells (Saos-2). Raman spectroscopy indicated significant amounts of collagen only in human bone-derived materials, where the mineral to protein ratio was 3.55 ± 0.

Combination of 3D Printing and ALD for Dentin Fabrication from Dental Pulp Stem Cell Culture.

A combination of fused deposition modeling printing with atomic layer deposition (ALD) of titania was designed to achieve templated biomineralization and terminal odontogenic differentiation of dental pulp stem cells on three-dimensional (3D) printed polylactic acid (PLA) scaffolds. In the absence of the ALD-deposited titania coating, we had previously shown that both plating efficiency and differentiation are adversely impacted when scaffolds are produced by 3D printing rather than traditional polymer molding. These differences were removed when both printed and molded structures were coated with ALD of titania, which improved the outcomes regardless of the manufacturing method.

Engineering functional skin constructs: A quantitative comparison of three-dimensional bioprinting with traditional methods.

Tissue engineering has been successful in reproducing human skin equivalents while incorporating new approaches such as three-dimensional (3D) bioprinting. The latter method offers a plethora of advantages including increased production scale, ability to incorporate multiple cell types and printing on demand. However, the quality of printed skin equivalents compared to those developed manually has never been assessed.

Synthesis of an Effective Flame-Retardant Hydrogel for Skin Protection Using Xanthan Gum and Resorcinol Bis(diphenyl phosphate)-Coated Starch.

We report on the production of a flame-resistant xanthan gum (XG)-based hydrogel formulation, which could be directly applied onto the skin for protection against burning projectiles. The hydrogel cream represents an efficient use of XG and starch, both of which are biodegradable, reusable natural materials and are also GRAS-certified. The flame-retardant agent resorcinol bis(diphenyl phosphate) (RDP) was shown to be nontoxic to cells in vitro when adsorbed directly onto the starch delivery vehicle.

The impact of TiO nanoparticle exposure on transmembrane cholesterol transport and enhanced bacterial infectivity in HeLa cells.

We have previously shown that exposure to TiO nanoparticles (NPs) reduces the resistance of HeLa cells to bacterial infection. Here we demonstrate that the increased infectivity is associated with enhanced asymmetry in the cholesterol distribution. We applied a live cell imaging method which uses tunable orthogonal cholesterol sensors to visualize and quantify in-situ cholesterol distribution between the two leaflets of the plasma membrane (PM).

Fibers Generated by Plasma Des-AA Fibrin Monomers and Protofibril/Fibrinogen Clusters Bind Platelets: Clinical and Nonclinical Implications.

 Soluble fibrin (SF) is a substantial component of plasma fibrinogen (fg), but its composition, functions, and clinical relevance remain unclear. The study aimed to evaluate the molecular composition and procoagulant function(s) of SF.  Cryoprecipitable, SF-rich (FR) and cryosoluble, SF-depleted (FD) fg isolates were prepared and adsorbed on one hydrophilic and two hydrophobic surfaces and scanned by atomic force microscopy (AFM).

Supervised machine learning approach to molecular dynamics forecast of SARS-CoV-2 spike glycoproteins at varying temperatures.

Abstract: Molecular dynamics (MD) simulations are a widely used technique in modeling complex nanoscale interactions of atoms and molecules. These simulations can provide detailed insight into how molecules behave under certain environmental conditions. This work explores a machine learning (ML) solution to predicting long-term properties of SARS-CoV-2 spike glycoproteins (S-protein) through the analysis of its nanosecond backbone RMSD (root-mean-square deviation) MD simulation data at varying temperatures.