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Synthetic dyes have gained much of the textile dyeing market by offering various colors. Synthetic dyes have been a worry for the environment owing to their hazardous nature running in parallel. In recent decades, there has been a movement to substitute natural compounds due to their biocompatibility, biodegradability, and biological advantages. This study investigated using Millettia Laurentii sawdust as a natural colorant source. Ecofriendly metal salts (aluminium sulfate, ferrous sulfate, and copper sulfate) under ecologically permitted concentration levels and biomordants (tannic acid, pine bark, oak fruit hull, and eucalyptus leaves) were used to broaden the color range (CIEL*a*b*C*ho and K/S) with significant improvements in the fastness attributes (washing, rubbing, and light) and UV protection properties. Fastness results were found in the commercially acceptable range. All the metal salts provided enhanced color yields with a maximum performance by iron and the corresponding ironbiomordant combinations (iron/pine bark and iron/oak fruit hull). Among the biomordants, pine bark extract provided better performance and higher color depth (9.16) than other biomordants. The findings of this research work showed a significant influence of metal salts and biomordants in combination with Millettia Laurentii sawdust (supposed to be a waste) for enhancing the color characteristics and functional attributes of wool yarns. [ABSTRACT FROM AUTHOR]

This work investigates the possibility of identification of natural dyes (madder and cochineal) and mordant types (Al, Sn, Cr, Cu, Fe) in dyed wool fibers using spectral imaging-based methods. For this purpose, technical imaging, including UVL, IRR and UVR, and obtained IRFC and UVFC images were used, along with multispectral imaging (350-1100 nm) and hyperspectral imaging (400-950 nm). The grayscales of multispectral and hyperspectral images were extracted to quantify the imaging data. The grayscale and the first derivative of the reflectance spectra obtained from the hyperspectral camera were investigated using multivariate principal component analysis and hierarchical clustering to separate the different groups of dyed fibers. According to results, aluminum and tin mordanted fibers could be distinguished from other groups as per UVL and IRFC images; similarly, the type of dye (madder or cochineal) was distinguishable from UVFC images. Interestingly, PCA analysis of grayscales of multispectral images provided an appropriate separation of all groups of fibers with different mordants and dyes. The 3d PCA plot and the hierarchical clustering of the first derivative of the reflectance spectra also resulted in better separation and classification of the dyed fiber groups. Nevertheless, the best performance in clustering fibers groups can be seen in the PCA analysis of grayscales obtained from hyperspectral images recorded at 430-830 nm. Therefore, hyperspectral imaging can be considered a more appropriate method for categorizing dyed fibers with different dyes and mordants. [ABSTRACT FROM AUTHOR]

Recently, natural dyes are being explored all over the world as safer and highly sustainable bio-based alternatives to synthetic dyes. Agricultural wastes and plant by-products are the most commonly explored alternatives with dual benefits of waste reclamation and sustainable dye production with extra value-adds. Hypercium scabrum plant contains interesting bio-dye molecules with high flavonoids and tannin contents. The present study aims at exploring the potential of H. scabrum plant extract to color wool textiles with a focus on sustainable bio-dye production and fastness properties. The extracted bio-dye was quantitatively (for total phenolic (2.733 mg per CE/g) and total flavonoid (1.140 mg per GAE/g) content using the Folin-Ciocalteu method) and qualitatively (UV-Vis, FT-IR, and EDX) characterized. The effect of dyeing parameters like pH (2-8), temperature (60-90 °C), dry-weight content of plant material as a dye (25-150% o.w.f.), and dyeing time (15-120 min) on color strength (K/S) values were assessed. Color fastness assays showed good resistance to light, washing, and rubbing. The effect of artificial aging (Xenon arc lamp) on the color strength of dyed wool yarns under different exposure times (0-48 h) was explored. The highest color fading occurred in control dyed samples with a first-order rate constant of 131.57 h -1 and a half-life period of 5.26 x 10 -3  h. Color difference (ΔE) values suggested that mordanted samples showed less fading compared to control dyed samples at equal times of Xenon exposure. Additionally, the dyed samples were washed in double distilled water, tap water, and 4 g/L NaCl solution to check their effects on the corresponding K/S values while 4 g/L NaCl solution mimics the real conditions of perspiration. Maximum color leaching occurred in 4 g/L NaCl washing with a first-order rate constant of 11.57 min -1 . Cost analysis of the dye extraction and dyeing procedure revealed that the process is sustainable and economical. Thus, the use of H. scabrum whole plant can provide a clean, economical, and sustainable source of alternative natural dyes that can be used to substitute synthetic analogs., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Modeling in molecular electronics is of great importance, and the use of semiconductor components for this type of modeling accelerates the development process in this field. In this work, a typical circuit model is proposed for modeling molecular components. Accordingly, an asymmetric oligo-phenylene vinylene (OPV) molecular diode and a bipyridine-biborinine molecular diode are modeled. A good agreement is observed between the current curves from the proposed circuit models and the atomic simulations of the molecules. Additionally, the electron density, the distribution of molecular orbitals, and the potential drop profile at + 1 and - 1 V are obtained and analyzed for the bipyridine-biborinine molecular diode using the density functional theory (DFT) in combination with the non-equilibrium Green's function (NEGF). Using different molecular gates and circuits based on the molecular devices, we have modeled the ternary NOT logic gate, ternary NOR logic gate, ternary NAND logic gate, negative ternary inverter (NTI) logic gate, positive ternary inverter (PTI) logic gate, ternary buffer, ternary decoder, and ternary half adder., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study presents a new approach to enhance reactive dye uptake and functional finishing of wool yarns via simple grafting with synthesized chitosan-acrylamide (Ch-Ac) hybrid. To this, Ch-Ac was synthesized and characterized with fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. Then, Ch-Ac was grafted on wool, characterized with FTIR, SEM, and weight gain analysis and dyeability with two commercial reactive dyes. Results showed that Ch-Ac treated wool could be dyed at lower temperatures (ca. 40 °C), times (ca. 30 min), and amount of reactive dye (2% owf) as compared to raw wool. Also, deeper shades not obtainable in conventional dyeing could be attained using Ch-Ac treated wool. In addition, Ch-Ac treatment imparted very good radical scavenging and excellent antibacterial activity against gram-negative (E. coli) and gram-positive (S. aureus) bacteria. Color fastness results confirmed that Ch-Ac treatment had no adverse effect on durability of dyes against washing, light, rubbing and perspiration. The results of this study clearly indicated that Ch-Ac can be used in eco-friendly functional finishing of wool with enhanced reactive dye uptake, minimized residual dye in wastewater, saving in consumption of chemicals, energy, and time of dyeing., (Copyright © 2019. Published by Elsevier B.V.)

Purpose: To determine the factors that influence the endothelial cell density (ECD) of donor grafts after Descemet stripping automated endothelial keratoplasty (DSAEK)., Methods: This retrospective, interventional case series comprised 77 eyes of 64 patients who underwent DSAEK. Confocal microscopy was performed at the final follow-up examination to evaluate the endothelial cell count, cell morphology, and graft thickness. Univariate and multiple linear regression analyses were used to investigate recipient-, donor-, surgical-, and postoperative related variables capable of influencing graft endothelial cell counts after DSAEK., Results: The mean patient age was 62.3 ± 15.6 years; patients were followed-up for 26.2 ± 20.9 months postoperatively. Forty-six eyes (59.7%) underwent stand-alone DSAEK; 31 eyes (40.3%) underwent DSAEK combined with cataract surgery. The donor trephination size was 8.0 ± 0.21 mm. The mean donor age was 30.4 ± 11.2 years, and the mean preoperative endothelial cell density was 3127.4 ± 315.1 cells/mm 2 , which decreased to 1788.6 ± 716.5 cells/mm 2 postoperatively ( P < 0.001). The mean postoperative central graft thickness was 102.4 ± 31.6 μm. Univariate analysis revealed that postoperative ECD was significantly associated with death to preservation time ( P = 0.046), graft thickness ( P = 0.016), follow-up duration ( P = 0.005), and graft non-attachment ( P = 0.049). Multiple regression analyses identified graft thickness (β = 10.62, P = 0.003) and follow-up duration (β = -22.09, P = 0.001) as the significant characteristics influencing postoperative ECD., Conclusion: The primary predictors of ECD after DSAEK were graft thickness and duration of follow-up. Surgeons' requests for ultrathin DSAEK donor grafts to improve visual outcomes might not have the desired postoperative outcome with respect to ECD., Competing Interests: There are no conflicts of interest.

Angiogenesis refers to new blood vessels that originate from pre-existing vascular structures. Corneal neovascularization which can lead to compromised visual acuity occurs in a wide variety of corneal pathologies. A large subset of measures has been advocated to prevent and/or treat corneal neovascularization with varying degrees of success. These approaches include topical corticosteroid administration, laser treatment, cautery, and fine needle diathermy. Since the imbalance between proangiogenic agents and antiangiogenic agents primarily mediate the process of corneal neovascularization, recent therapies are intended to disrupt the different steps in the synthesis and actions of proangiogenic factors. These approaches, however, are only partially effective and may lead to several side effects. The aim of this article is to review the most relevant treatments for corneal neovascularization available so far.

Novel naphthalimide-poly(amidoamine) dendrimer fluorescent dyes were synthesized, and their structures were identified and confirmed using different characterization methods such as Fourier transform infrared, (1) H NMR, (13) C NMR, differential scanning calorimetry, elemental analysis and UV-vis spectroscopy. The spectrophotometric studies demonstrated absorption maxima (λmax ) and extinction coefficient (εmax ) values in the ranges of 429-438 nm and 25,635-88,618 L/mol/cm, respectively. The dyeing, fastness and antimicrobial properties of dyed wool fibers were examined. Colorimetric measurements demonstrated a greenish-yellow hue with remarkable fluorescence intensity on dyed wool. Although the fastness properties of naphthalimide dye on wool fibers were poor/moderate, color fastness was appreciably improved through modification of the dye using dendrimers. The results revealed that the newly synthesized dyes are potent antimicrobial agents on wool fibers. Overall, it was deduced that poly(amidoamine) (PAMAM) dendrimers could be exploited as a promising tool in tailoring the different properties of naphthalimide dyes, being suitable for dyeing and antimicrobial finishing agents for wool fibers. Copyright © 2015 John Wiley & Sons, Ltd., (Copyright © 2015 John Wiley & Sons, Ltd.)