Boosting Supramolecular Gelation Efficiency and Properties: Ionic Strength as a Key to Superior Hydrogels.

Controlling the minimum gelation concentration (MGC) of low molecular weight (LMW) hydrogelators is a key for modulating gel properties, such as mechanical strength, viscoelasticity, and stability, which are crucial for applications ranging from drug delivery to tissue engineering. However, tweaking the MGC under specific conditions, such as pH and/or temperature, poses a considerable challenge. Herein, we varied the ionic strength of buffer solutions using NaCl for several LMW hydrogelators, including Fmoc-Phe, Fmoc-Tyr, Fmoc-Trp, Fmoc-Met, and Fmoc-Cha, and assessed their gelation efficiency at pH 7.

Rheological and dielectric behavior of sodium carboxymethyl cellulose (NaCMC)/Ca and esterified NaCMC/Ca hydrogels: Correlating microstructure and dynamics with properties.

Polyelectrolyte-based conductive hydrogels are being extensively explored for applications in energy storage and as electrode materials for batteries. We synthesized ionically crosslinked sodium carboxymethyl cellulose (NaCMC), esterified NaCMC, and Ca doped esterified NaCMC hydrogels. This work aims to understand the effect of Ca ions on the NaCMC and esterified NaCMC.

A Unique Temperature-Induced Reverse Supramolecular Chirality-Assisted Gel-to-Gel Transition.

Supramolecular hydrogels typically undergo a gel-to-sol transition with heat, as intermolecular interactions within the gel weaken. Although gel-to-gel transitions during heating are rare, they may occur due to minor rearrangements caused by thermal forces in the supramolecular self-assembled structure. Here, an unprecedented temperature-induced gel-to-gel transition assisted by supramolecular chiral inversion in a hydrogel system is presented.

The Personality and Resilience of Competitive Athletes as BMW Drivers-Data from India, Latvia, Lithuania, Poland, Romania, Slovakia, and Spain.

Background: Individual differences in personality and resilience are related to a variety of social behaviors. The current study sought to answer the question of whether BMW drivers exhibit different personality profiles and resilience levels compared with drivers of other car brands.

Participants And Procedure: An international study was carried out in India, Latvia, Lithuania, Poland, Romania, Slovakia, and Spain on a sample of 448 athletes using the 20-item Mini-IPIP and the Resilience Scale.

Electrostatic Heteroaggregation: Fundamentals and Applications in Interfacial Engineering.

The aggregation of oppositely charged soft materials (particles, surfactants, polyelectrolytes, etc.) that differ in one or more physical or chemical attributes, broadly referred to as electrostatic heteroaggregation, has been an active area of research for several decades now. While electrostatic heteroaggregation (EHA) is relevant to diverse fields such as environmental engineering, food technology, and pharmaceutical formulations, more recently there has been a resurgence to explore various aspects of this phenomenon in the context of interface stabilization and the development of functional materials.

π-System Functionalization Transforms Amyloidogenic Peptide Fragment of Human Islet Amyloid Polypeptide into a Super Hydrogelator.

While a considerable number of ultra-short/short amyloid peptides have been reported to form 3D supramolecular hydrogels, they all possess high minimum gelation concentration (MGC) (≥1 wt%), which preclude their applications. In this context, we demonstrate that functionalisation of a well-known amyloidogenic ultra-short peptide fragment NFGAIL (IAPf) of human Islet amyloid polypeptide with a π-system (Fluorenyl, Fm) at the N-terminus of the peptide (Fm-IAPf) yield not only highly thermostable hydrogel at physiological pH but also exhibited super gelator nature as the MGC (0.08 wt%) falls below 0.

Multiscale Approach to Studying Biomolecular Interactions in Cellulose-Casein Adhesion.

Casein finds application as an eco-friendly adhesive for paper, wood, glass, etc. Casein being a protein can undergo conformational and microstructural changes during various processing steps involved in interfacial bonding. This study aims at understanding the multiscale contributions of these changes in casein to its adhesion to cellulose pressboards.

A "self-shrinking" supramolecular hydrogel with a 3D shape memory performance from an unnatural amino acid derivative.

A supramolecular hydrogel with 3D self-shrinking, without any assistance, and a shape memory performance at room temperature is discovered from an unnatural amino acid derivative, fluorenylmethoxycarbonyl-L-β-phenylalanine, as a minimalistic model. The self-shrinking properties of this hydrogel can be explored for potential applications.

Pectin self-assembly and its disruption by water: insights into plant cell wall mechanics.

Plant cell walls undergo multiple cycles of dehydration and rehydration during their life. Calcium crosslinked low methoxy pectin is a major constituent of plant cell walls. Understanding the dehydration-rehydration behavior of pectin gels may shed light on the water transport and mechanics of plant cells.

Contributions from microstructural changes to the rheological behavior of casein dispersions during drying.

In several applications, a protein such as casein in dispersion form undergoes multiple processing steps including drying. In this work, the rheological and microstructural features of casein dispersions concentrated by evaporation of the solvent (drying dispersions) were studied in comparison with those of equal concentrations of the as-prepared dispersions without drying. The molecular assembly of casein is affected by drying along with the conformational composition changes in the secondary structures such as α-helix, β-sheets, turns and random structures of the protein.

Fibrillar Network Dynamics during Oscillatory Rheology of Supramolecular Gels.

Supramolecular gels are three-dimensional network structures formed by the hierarchical self-assembly of small molecules through weak noncovalent interactions. On the basis of the various interactions contributed by specific functional groups/moieties, gels with different architectures can be constructed that are smart to the external stimuli such as pH, type of solvent, stress, temperature, etc. In the present work, we explore the oscillatory shear response of supramolecular self-assembled systems formed by the low-molecular-weight (LMW) gelator based on difunctionalized amino acid, florenylmethoxycarbonyl (Fmoc)-lysine(Fmoc), Fm-K(Fm) in aqueous buffer solution, at two different pH (6 and 7.

Self-healing microcapsules encapsulated with carbon nanotubes for improved thermal and electrical properties.

Microcapsules are widely used by researchers in self-healing composites. In this study, multi-walled carbon nanotubes (CNT) were incorporated into the core of the microcapsules, along with the self-healing agent. Dicyclopentadiene (DCPD) and urea-formaldehyde (UF) were chosen as the core and shell materials respectively, and DCPD-CNT-UF based dual core microcapsules were synthesized.

Influence of reduced graphene oxide on flow behaviour, glass transition temperature and secondary crystallinity of plasticized poly(vinyl chloride).

Understanding the rheological behaviour of thermoplastic nanocomposites is important to obtain a concrete knowledge of their processability. The viscoelastic properties of nanocomposites are a reflection of their morphology. The study of flow and deformation of nanocomposites provides essential information related to prevalent interactions in the system as well as contribution from the dispersion of incorporated nanofillers.

A randomized, double blind, placebo controlled study to evaluate the effects of ashwagandha (Withania somnifera) extract on sleep quality in healthy adults.

Objective: Non-restorative sleep (NRS) affects 10% people worldwide, leading to poor sleep quality, as well as physical and cognitive fatigue. This is the first human study in which an extract of ashwagandha (Withania somnifera Dunal L.) was evaluated for effects in improving overall sleep quality in subjects with NRS.

Non-proteinogenic amino acid based supramolecular hydrogel material for enhanced cell proliferation.

Supramolecular gel material built from low-molecular-weight (LMW) gelators finds potential applications in various fields, especially in drug delivery, cell encapsulation and delivery, and tissue engineering. The majority of the LMW gelators in these applications are based on functionalized peptides/amino acids consisting of proteinogenic amino acids which are proteolytically unstable. Herein, we have developed a new LMW gelator containing non-proteinogenic amino acid namely 2,3-diaminopropionic acid (Dap), a key precursor in the synthesis of many antibiotics namely viomycin and capreomycin, by functionalizing with fluorenylmethoxycarbonyl at both amino terminals of Dap [Fm-Dap(Fm)].

Dissipation and strain-stiffening behavior of pectin-Ca gels under LAOS.

Non-linear mechanical responses observed in networks of many biopolymers such as pectin are important for their functioning as biological systems. Additionally, pectins derived from plant sources are also used for several food and biomedical applications. In the present work, the possible contributions of egg-box bundles in the large deformation response of calcium crosslinked gels of low methoxy pectin are explored using large amplitude oscillatory shear (LAOS).

A three-dimensional finite element analysis of the influence of varying implant crest module designs on the stress distribution to the bone.

Background: The aim of this study is the effect of stress distribution within the bone with varying implant crest module designs.

Materials And Methods: Finite element models of a straight two-piece 4 mm × 13 mm screw-shaped threaded implant with divergent, straight, and convergent implant crest module with their surrounding suprastructure embedded in mandibular second premolar area were created with ANSYS software. Different implant crest module designs incorporated in D2 types of bone under 100N axial and 100N at 20° oblique load were created to evaluate stress distribution in the crestal bone around implant crest module.

Rheology and microstructure of concentrated microcrystalline cellulose (MCC)/1-allyl-3-methylimidazolium chloride (AmimCl)/water mixtures.

Water added to a solution of microcrystalline cellulose (MCC) in 1-allyl-3-methylimidazolium chloride (AmimCl) reduces the solvent quality and causes significant changes in the flow properties and microstructure due to restructuring and aggregation of cellulose molecules. We report an experimental investigation by means of polarization optical microscopy (POM) and rheology of the distinct phases formed in 5-20 wt% MCC/AmimCl solutions due to the addition of water. With increase in the cellulose concentration, the MCC/AmimCl/water mixtures showed different morphologies such as the non-aligned cholesteric liquid crystalline (LC) domain, the coexistence of spherulite-like structures within the LC domain and a space-spanning network of spherulite-like structures at high concentrations of water.

Study protocol and rationale for a prospective, randomized, double-blind, placebo-controlled study to evaluate the effects of Ashwagandha (Withania somnifera) extract on nonrestorative sleep.

Unlabelled: Nonrestorative sleep (NRS) is one of the cardinal symptoms of insomnia and can occur independent of other components of insomnia. Among the sleep disturbances, NRS has been little studied in the general population, even though this symptom plays an important role in several medical conditions associated with chronic inflammation such as heart disease, fibromyalgia, and chronic fatigue syndrome, as well as various sleep disorders. There is paucity in the literature about effective treatments for NRS.

Kosmotropic effect leads to LCST decrease in thermoresponsive polymer solutions.

We study the phenomena of decrease in lower critical solution temperature (LCST) with addition of kosmotropic (order-making) cosolvents in thermoresponsive polymer solutions. A combination of explicit solvent coarse-grained simulations and mean-field theory has been employed. The polymer-solvent LCST behavior in the theoretical models has been incorporated through the Kolomeisky-Widom solvophobic potential.

Enhanced mobility of non aqueous phase liquid (NAPL) during drying of wet sand.

Enhanced upward mobility of a non aqueous phase liquid (NAPL) present in wet sand during natural drying, and in the absence of any external pressure gradients, is reported for the first time. This mobility was significantly higher than that expected from capillary rise. Experiments were performed in a glass column with a small layer of NAPL-saturated sand trapped between two layers of water-saturated sand.

A Low-Molecular-Weight Gelator Composed of Pyrene and Fluorene Moieties for Effective Charge Transfer in Supramolecular Ambidextrous Gel.

Charge-transfer (CT) gel materials obtained from low-molecular-weight (LMW) compounds through a supramolecular self-assembly approach have received fascinating attention by many researchers because of their interesting material property and potential applications. However, most of the CT gel materials constructed were of organogels while the construction of CT gels in the form of a hydrogel is a challenge because of the solubility issue in water, which considerably limits the use of CT hydrogels. Herein, for the first time, we report a new LMW gelator [N-(fluorenylmethoxycarbonyl)-N-(δ-butyric-1-pyrenyl)-l-lysine, (FmKPy)], composed of two functional moieties such as fluorenylmethoxycarbonyl and pyrene, which not only parade both hydro and organo (ambidextrous) supramolecular gel formation but also exhibit CT ambidextrous gels when mixed with an electron acceptor such as 2,4,7-trinitro-9-fluorenone (TNF).

Molecular Structuring and Percolation Transition in Hydrated Sulfonated Poly(ether ether ketone) Membranes.

The extent of phase separation and water percolation in sulfonated membranes are the key to their performance in fuel cells. Toward this, the effect of hydration on the morphology and transport characteristics of sulfonated poly(ether ether ketone), sPEEK, membrane is investigated using atomistic molecular dynamics simulation at various hydration levels(λ: number of water molecules per sulfonate group). The evolution of local morphology is investigated using structural correlations and minimum pair distances.

Hetero-aggregation of oppositely charged nanoparticles.

Hetero-aggregation refers to aggregation of particles that are not identical i.e. particles of different physical-chemical properties.