Publications by authors named "Muthukumar M"

The elastic and fracture properties of hydrogels are strongly influenced by the polymer network structure. The hydrogel network is similar to the extracellular matrix (ECM) of tissues. The network structure of the hydrogel can be varied by varying the polymer volume fraction () and crosslinker concentration ().

View Article and Find Full Text PDF

Objectives: Our aim was to review the evidence for the cost effectiveness of elective surgeries with long waiting lists within the NHS in England. This is to inform understanding of national spending priorities in the context of significant demand for elective surgeries and to inform the debate on appropriate cost-effectiveness thresholds across healthcare decision making.

Methods: We conducted a targeted literature review to identify published cost-effectiveness analyses for nine elective procedures with long waiting lists in the NHS, selected based on previous reviews.

View Article and Find Full Text PDF

Survey conducted during February and May 2023 in the rice growing regions of Chengalpattu and Kanchipuram districts of Tamil Nadu, India, revealed that Chengalpattu district had brown spot incidence ranging from 10.6 % to 89 %. Maximum of 89 PDI (percent disease incidence) was observed in the farm of SRM College of Agricultural Sciences, Chengalpattu District, Tamil Nadu, India.

View Article and Find Full Text PDF

Response of polar and neutral monomers in macromolecules to an electric field in their crowded aqueous solutions remains as an unchartered area of research, in contrast with well understood behavior of ionized groups. Wondering whether such monomers impart merely frictional resistance or cooperate with the other ionic groups in their electrophoretic mobility, we investigate single-molecule electrophoresis of a couple of neutral polyzwitterions which have charge-neutrality with strong acidic group and permanent positive charge within their repeat units. Combining experiments and theory, we study the roles of dipole orientation of zwiterionic monomers and salt identity.

View Article and Find Full Text PDF

Gels comprised of dynamic bonds are important candidates for the emerging 'intelligent' gels due to their unique characteristics. We report a universal law of hierarchical gel dynamics arising from association-dissociation of physical crosslinks, as discerned from dynamic light scattering (DLS) on diverse sets of complex gels. It is the first experimental evidence of a stretched exponential decay with a universal exponent 1/3 in DLS for all the physical gels, complementing more than five decades of DLS studies on conventional chemical gels.

View Article and Find Full Text PDF

Direct translocation of RNA with secondary structures using single-molecule electrophoresis through protein nanopores shows significant fluctuations in the measured ionic current, in contrast to unstructured single-stranded RNA or DNA. We developed a multiscale model combining the oxRNA model for RNA with the 3-dimensional Poisson-Nernst-Planck formalism for electric fields within protein pores, aiming to map RNA conformations to ionic currents as RNA translocates through three protein nanopores: α-hemolysin, CsgG, and MspA. Our findings reveal three distinct stages of translocation (pseudoknot, melting, and molten globule) based on contact maps and current values.

View Article and Find Full Text PDF

Conformations and dynamics of an intrinsically disordered protein (IDP) depend on its composition of charged and uncharged amino acids, and their specific placement in the protein sequence. In general, the charge (positive or negative) on an amino acid residue in the protein is not a fixed quantity. Each of the ionizable groups can exist in an equilibrated distribution of fully ionized state (monopole) and an ion-pair (dipole) state formed between the ionizing group and its counterion from the background electrolyte solution.

View Article and Find Full Text PDF

We introduce a theoretical framework to describe the pH-sensitive phase behavior of polyzwitterion-polyelectrolyte complex coacervates that reasonably captures the phenomenon from recent experimental observations. The polyzwitterion is described by a combinatorial sequence of the four states in which each zwitterionic monomer can occupy: dipolar, quasi-cationic, quasi-anionic, and fully neutralized. We explore the effects of various modifiable chemical and physical properties of the polymers-such as, p of the pH-active charged group on the zwitterion, equilibrium constant of salt condensation on the permanently charged group on the zwitterion, degrees of polymerization, hydrophobicity ( the Flory-Huggins interaction parameter), and dipole lengths-on the window of complexation across many stoichiometric mixing ratios of polyzwitterion and polyelectrolyte.

View Article and Find Full Text PDF

The synthesis of diversely substituted quinazoline-2,4(1,3)-diones by cyclization of -butyl (2-cyanoaryl)carbamates using readily accessible Boc protected -amino nitriles is reported. The reaction proceeds smoothly at room temperature using 1 equiv. of HO under basic conditions.

View Article and Find Full Text PDF
Article Synopsis
  • - The study develops a theoretical framework to analyze thermoreversible phase transitions in polyzwitterion systems, which includes macrophase separations and gelation effects.
  • - It uses mean-field percolation and field theory to derive the Landau free energy based on factors like concentration, temperature, and salt levels, demonstrating how decreasing temperature promotes polyzwitterion cross-linking and associational networks.
  • - The research reveals that these associations alter critical behaviors, with discovered critical exponents deviating from Ising universality, indicating unique crossover critical behaviors in the system.
View Article and Find Full Text PDF

Background: The first evidence of blood biochemical and proteomic changes in slow-growing broiler chicken subjected to ritual slaughter like halal (HS) and jhatka (JS) without stunning and commercial slaughter with electrical stunning (ES) was decoded.

Results: Significant stress indicators like cortisol and triiodothyronine were markedly elevated in JS birds, whereas increased (P < 0.05) levels of lactate dehydrogenase and creatine kinase were observed in JS and ES birds.

View Article and Find Full Text PDF

Nowadays, volatile organic compound (VOC) detection is imperative to ensure environmental safety in industry and indoor environments, as well as to monitor human health in medical diagnosis. Gas sensors with the best sensor response, selectivity, and stability are in high demand. Simultaneously, the advancement of nanotechnology facilitates novel nanomaterial-based gas sensors with superior sensor characteristics and low power consumption.

View Article and Find Full Text PDF

The behavior of polyzwitterions, constituted by dipole-like zwitterionic monomers, is significantly different from that of uniformly charged polyelectrolytes. The origin of this difference lies in the intrinsic capacity of polyzwitterions to self-associate intramolecularly and associate with interpenetrating chains driven by dominant dipolar interactions. Earlier attempts to treat polyzwitterions implicitly assume that the dipoles of zwitterion monomers are randomly oriented.

View Article and Find Full Text PDF

A visible-light-mediated trifluoromethylation protocol was developed for the conversion of (hetero)aromatic thiols to their respective -trifluoromethylated derivatives employing trifluoromethanesulfonyl chloride (CFSOCl) as a cost-effective source of trifluoromethyl radical (CF·) and a highly reducing organophotocatalyst, 3DPA2FBN. The developed methodology is operationally simple, providing access to a diverse range of products in up to 92% yield. A plausible mechanism has been postulated based on preliminary mechanistic studies, including irradiation on/off, UV-vis studies, and radical trapping experiments.

View Article and Find Full Text PDF

Background: Peripheral Intravenous Cannulas (PIVCs) are frequently utilised in the Emergency Department (ED) for delivery of medication and phlebotomy. They are associated with complications and have an associated cost to departmental resources. A growing body of international research suggests many of the PIVCs inserted in the ED are unnecessary.

View Article and Find Full Text PDF

We study the role of active coupling on the transport properties of homogeneously charged macromolecules in an infinitely dilute solution. An enzyme becomes actively bound to a segment of the macromolecule, exerting an electrostatic force on it. Eventually, thermal fluctuations cause it to become unbound, introducing active coupling into the system.

View Article and Find Full Text PDF

We formed core-shell-like polyelectrolyte complexes (PECs) from an anionic bottlebrush polymer with poly (acrylic acid) side chains with a cationic linear poly (allylamine hydrochloride). By varying the pH, the number of side chains of the polyanionic BB polymers (N), the charge density of the polyelectrolytes, and the salt concentration, the phase separation behavior and salt resistance of the complexes could be tuned by the conformation of the BBs. By combining the linear/bottlebrush polyelectrolyte complexation with all-liquid 3D printing, flow-through tubular constructs were produced that showed selective transport across the PEC membrane comprising the walls of the tubules.

View Article and Find Full Text PDF

The mouth houses the second largest diversity of microorganisms in the body, harboring more than 700 bacterial species colonizing the soft mucosa and hard tooth surfaces. Microbes are the cause of several health-related problems, such as dental carries, gingivitis, periodontitis, etc., in the mouth across different age groups and socioeconomic/demographic groups.

View Article and Find Full Text PDF

Electro-osmotic flow (EOF) is a phenomenon where fluid motion occurs in porous materials or micro/nano-channels when an external electric field is applied. In the particular example of single-molecule electrophoresis using single nanopores, the role of EOF on the translocation velocity of the analyte molecule through the nanopore is not fully understood. The complexity arises from a combination of effects from hydrodynamics in restricted environments, electrostatics emanating from charge decorations and geometry of the pores.

View Article and Find Full Text PDF

When a solution of interpenetrating and entangled long flexible polymer chains is cooled to low enough temperatures, the chains crystallize into thin lamellae of nanoscopic thickness and microscopic lateral dimensions. Depending on the nature of the solvent and growth conditions, the lamellae exhibit several sectors that have differing growth kinetics and melting temperatures. Remarkably, these lamellae can spontaneously form tentlike morphology.

View Article and Find Full Text PDF

An innovative tissue culture mediated incorporation of metabolite-based biomolecule (Bio-immune) at stage itself in banana cv. Grand Naine was developed and validated for the production of f.sp.

View Article and Find Full Text PDF

Background: Retinopathy of prematurity (ROP) is a vasculoproliferative disorder of immature retina, seen in preterm babies. Multiple risk factors attribute to this condition. Our aim was to correlate the role of any early neonatal surgeries with low gestational age (GA) and birth weight (BW) on preterm babies as a risk factor on the progression of ROP.

View Article and Find Full Text PDF

is a flowering plant belonging to a genus of the dicotyledonous herbaceous annual flowering plant of the Asteraceae (Compositae) family. It is a perpetual flowering plant, mostly cultivated for medicinal purposes; generally, used in popular drinks due to its aroma and flavor. It is primarily cultivated in China, Japan, Europe, and United States.

View Article and Find Full Text PDF

Aqueous solutions of oppositely charged macromolecules exhibit the ubiquitous phenomenon of coacervation. This subject is of considerable current interest due to numerous biotechnological applications of coacervates and the general premise of biomolecular condensates. Towards a theoretical foundation of structural features of coacervates, we present a field-theoretic treatment of coacervates formed by uniformly charged flexible polycations and polyanions in an electrolyte solution.

View Article and Find Full Text PDF

Leaves of jamun collected as agro by-produce during the cultivation of jamun is traditionally used as ayurvedic medicine to treat diabetes, gall bladder stones and other ailments. Most of the beneficial effects of jamun leaves are associated with phytochemicals found in jamun leaves such as gallic acid, tannins, mallic acid, flavonoids, essential oils, jambolin, ellagic acid, jambosine, antimellin and betulinic acid. Jamun possess curative activities like anticancer, antidiabetic, antifertility, anti-inflammatory, antidiarrheal, antimicrobial, antinociceptive, antioxidant, antiradiation, chemotherapeutic, and gastroprotective.

View Article and Find Full Text PDF