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• Four dyes extracted from 'natural' sources were investigated for their suitability as LDS materials. • Selected natural dyes showed desired stokes shifts to harvest the incident photons of short wavelengths. • LDS dyes based on Curcuma longa L. and Moringa Oleifera showed a noteworthy enhancement in the light-harvesting efficiency. The short wavelength photons (below 500 nm) of the solar spectrum are under-utilized in multicrystalline silicon (mc-Si) solar modules because of their high surface recombination losses. The application of luminescent down-shifting (LDS) materials is an effective way to utilize the short wavelength photons to enhance the efficiency of a mc-Si solar module. This study utilized four 'natural' dyes extracted from the wheat husk, rice husk, turmeric rhizomes (Curcuma longa L.), and Moringa Oleifera leaves for LDS application. These natural dyes showed absorption in the UV and blue range, and emission in the visible range which is effectively utilized by the silicon solar cell. Optimum concentrations of the natural dyes were incorporated in the front ethylene vinyl acetate (EVA) layers which were used to encapsulate bare Si cells into photovoltaic (PV) modules. The mc-Si PV modules which had the front encapsulation of EVA films containing the turmeric and moringa dyes showed relative enhancement of ~ 6.8% (±3.6) and ~ 9% (±4) respectively, in their efficiencies with respect to that of the corresponding bare silicon cells. The gains in the photovoltaic efficiency obtained with the turmeric and moringa dyes were found to be comparable to (or slightly greater than) the values reported in the literature using various Eu3+ based lanthanide complexes as LDS materials. Finally, the inclusion of natural LDS dyes in the encapsulating EVA layer would offer an economical and pro-environmental solution at high volume manufacturing to improve the utilization of short-wavelength photons. [ABSTRACT FROM AUTHOR]

[Display omitted] • A 3D COMSOL based mathematical model for an internal active cooling mechanism was developed and validated. • Internal active air cooling was found to reduce the temperature of a Si solar cell further by at least 5 °C when compared with conventional external convection. • Internal active cooling is expected to result into 9.6 % net gain in the output of a solar power plant. Renewable energy sources are experiencing a resurgence in popularity due to growing environmental concerns. Solar technologies are the best renewable energy alternatives for meeting ever-increasing energy demand. The photovoltaic (PV) modules installed in a solar power plant get heated up quickly, resulting in significant reduction in their operating efficiency. This paper presents a mathematical model and its validation for a novel 'internal' active cooling mechanism, proposed elsewhere, for lowering the temperature of a crystalline silicon PV module. Specifically, a 3D mathematical model using COMSOL Multiphysics® software was developed to predict a silicon solar cell's temperature for conventional external and proposed internal cooling methods. The developed model was validated with the experimental data borrowed from the patent application (no. 202211050095). When compared to external air convection at a flow rate of 2 m/s, the proposed internal cooling method reduced the temperature of a Si solar cell by at least 5 °C. Finally, an economic analysis revealed that internal cooling could result in a 9.6 % net gain in the output of a solar power plant, compared to the 4.6 % net gain offered by external air cooling. [ABSTRACT FROM AUTHOR]

MethylCpG binding protein-2 (MeCP2) is an epigenetic regulator and essential for brain development. MeCP2 mutations are associated with a spectrum of neuro-developmental disorders that vary depending on the patient gender, most notably Rett Syndrome. MeCP2 is essential for normal neuronal maturation, and glial cell function in the brain. Besides, its role in neurodevelopmental disorders, MeCP2 is involved in many cancers such as breast, colorectal, lung, liver, and prostate cancer. Glioma is the most lethal form of brain cancer. Studies have shown that dysfunctional epigenetic regulation plays a crucial role in glioma progression. Further, previous studies have suggested a role for MeCP2 in glioma pathogenesis. In this study, we show that MeCP2 may play a critical role in the suppression of glioma progression. Stable overexpression of MeCP2in C6 glioma cells inhibits proliferation, migration, invasion, and adhesion. Moreover, MeCP2 overexpression inhibits pERKand BDNF expression while inducing GFAP expression in C6 glioma. These findings suggest that MeCP2 may play a crucial role in suppression of glioma progression. [ABSTRACT FROM AUTHOR]

Topical approaches to oral diseases require frequent dosing due to limited retention time. A mucoadhesive drug delivery platform with extended soft tissue adhesion capability of up to 7 days is proposed for on-site management of oral wound. Bacterial cellulose (BC) and photoactivated carbene-based bioadhesives (PDz) are combined to yield flexible film platform for interfacing soft tissues in dynamic, wet environments. Structure-activity relationships evaluate UV dose and hydration state with respect to adhesive strength on soft tissue mimics. The bioadhesive composite has an adhesion strength ranging from 7 to 17 kPa and duration exceeding 48 h in wet conditions under sustained shear forces, while other mucoadhesives based on hydrophilic macromolecules exhibit adhesion strength of 0.5–5 kPa and last only a few hours. The work highlights the first evaluation of BC composites for mucoadhesive treatments in the buccal cavity. [Display omitted] • Bacterial cellulose (BC) physically modified into a light-activated bioadhesive • Cellulose composites evaluated for adhesive properties to wet mucosal tissues • Structure property evaluation-BC film type, joules light dose, hydration state • Composites exhibited 2–5 times higher adhesion strength than existing formulations • Composites achieved retention times of 2–7 days in harsh, dynamic environments [ABSTRACT FROM AUTHOR]

[Display omitted] • Acrylate-based hybrid polymer networks lack material design flexibility. • Diazirine-grafted polyol, a novel carbene crosslinker of hybrid networks. • Diazirine remains unreacted during thiol/ene crosslinking reaction. • Carbene enables high level of control over hybrid network material properties. Thiol/ene-based resorbable elastomers display tough elongation but lack adhesion to soft tissues. Carbene-based bioadhesives (e.g. CaproGlu) allow soft tissue adhesion, but the covalent crosslinks limit extensibility after photoactivation. Herein thiol/ene resorbable elastomers are combined with a carbene bioadhesive into a 3-component hybrid network by exploiting tunable photoactivation of each macromolecule independently or simultaneously. Dual crosslinking was monitored by photorheometry, where 405 nm initiates formation of a thiol/ene elastomeric network, followed by 365 nm activation of diazirine-grafted polycaprolactone tetrol (CaproGlu). Dynamic shear moduli, gelation point, elongation at break, and lap shear stress of the hybrid polymer network are evaluated with respect to absorbed light energy dose. Surface-exposed unreacted CaproGlu enables adhesion of the hybrid network to various substrates, as well as intermolecular crosslinking within the transparent matrix. The network morphology and functional group conversion is evaluated through scanning electron microscopy and infrared spectroscopy, respectively. For the first time, we demonstrate hybrid thiol/ene/diazirine double sided bioadhesives with tunable dynamic moduli in the range of 10–800 kPa and 160 kPa lap-shear adhesion strength. [ABSTRACT FROM AUTHOR]

Antibiotic resistance via epigenetic methylation of ribosomal RNA is one of the most prevalent strategies adopted by multidrug resistant pathogens. The erythromycin-resistance methyltransferase (Erm) methylates rRNA at the conserved A2058 position and imparts resistance to macrolides such as erythromycin. However, the precise mechanism adopted by Erm methyltransferases for locating the target base within a complicated rRNA scaffold remains unclear. Here, we show that a conserved RNA architecture, including specific bulge sites, present more than 15 Å from the reaction center, is key to methylation at the pathogenic site. Using a set of RNA sequences site-specifically labeled by fluorescent nucleotide surrogates, we show that base flipping is a prerequisite for effective methylation and that distal bases assist in the recognition and flipping at the reaction center. The Erm-RNA complex model revealed that intrinsically flipped-out bases in the RNA serve as a putative anchor point for the Erm. Molecular dynamic simulation studies demonstrated the RNA undergoes a substantial change in conformation to facilitate an effective protein-rRNA handshake. This study highlights the importance of unique architectural features exploited by RNA to impart fidelity to RNA methyltransferases via enabling allosteric crosstalk. Moreover, the distal trigger sites identified here serve as attractive hotspots for the development of combination drug therapy aimed at reversing resistance. [ABSTRACT FROM AUTHOR]

• Nanocolloidal micelles (LP-PMs) were prepared to deliver hydrophobic drug, lapatinib. • Addition of Pluronic® F127 reduces the critical micelle concentration of Soluplus®. • Nanosize (<100 nm) indicated tumor targeting potential of LP-PMs by passive method. • Resistance to dilution and platelet aggregation proves I.V. administration aptness. • Encapsulation inside micelle core improved anticancer efficacy and reduced hemolysis. Nanocolloids are considered ideal carriers for hydrophobic drugs owing to their core–shell structure. Lapatinib is a potential anti-cancer agent, but its clinical use is limited because of its poor aqueous solubility, thus requiring larger oral doses with the associated toxicity. Thus, in the present study, we fabricated self-assembled nanocolloidal polymeric micelles (LP-PMs) of Soluplus® and Pluronic® F127 by the thin-film hydration method and assessed their delivery potential of the hydrophobic anti-cancer drug lapatinib (LP) and optimised these nanocolloidal polymeric micelles using Quality-by-Design approach. Amorphisation of the drug and no typical incompatibility other than hydrogen bonding in the LP-PMs was confirmed by solid-state characterisation. The LP-PMs exhibited a uniform size of 92.9 ± 4.07 nm, with a 5.06 mV zeta potential and approximately 87% drug encapsulation. The critical micellar concentration (CMC) of Soluplus® decreased from 6.63 × 10−3 to 4.4 × 10−3 mg/mL by incorporating Pluronic® F127. Further, the sustained release of LP from the LP-PMs was confirmed by in-vitro release studies showing 36% and 60% of LP released from the LP-PMs within 48 h in release media of pH 7.4 and pH 5.0, respectively. These results support their capability of preferential release at acidic tumor environment. Their hemocompatibility evidenced by hemolysis below accepted limits and no platelet aggregation with resistance to instant dilution illustrated their admirable blood compatibility and suitability for intravenous administration. The encapsulation of LP inside micelles enhanced the cytotoxicity of LP against SKBr3 breast cancer cells. Further, the LP-PMs were found to be stable over six months when stored at 2–8 °C. These findings indicate the improved potential of nanocolloidal polymeric micelles as promising carriers for the preferential and sustained delivery of hydrophobic anticancer drugs such as lapatinib to tumours. [ABSTRACT FROM AUTHOR]