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• Smart conducting polymer-GQD composites synthesised through ex-situ and in-situ routes. • Polymer-filler interface quality found dependant on fabrication route. • Ex-situ composite suitable for opto-electronic display while in-situ composite suitable as energy harvestor. This article elucidates fabrication of a smart composite from poly (3-bromothiophene) (PTBr) and graphene quantum dot (GQD) through facile in-situ and ex-situ routes and demonstrates their photo-physical and photo-electrochemical behaviors. 3-bromothiophene was first polymerized to poly (3-bromothiophene) (PTBr) in presence of graphene oxide (GO) and then converted into PTBr/GQD composite through solvo-thermal route in the in-situ process while in the ex-situ process, both graphene oxide (GO) and poly (3-bromothiophene) (PTBr) were first combined ex-situ and then solvo-thermally treated to fabricate the PTBr/GQD composite. Spectroscopic findings indicate safe formation of the composites however, alteration in both precursor and fabrication route had simultaneously created a demonstrable difference in interfacial interaction between poly (3-bromothiophene) (PTBr) and graphene quantum dot (GQD) which eventually impacted their application behavior. Microscopy, Energy dispersive X-Ray (EDX) mapping and X-ray diffraction study mutually elucidated the formation of uniformly thin, fibrillar (8 nm) over-growth of amorphous poly (3-bromothiophene) (PTBr) over graphene quantum dot (GQD) in the ex-situ composite while in the in-situ composite a comparatively non-uniform and thicker over-growth (12 nm) of poly (3-bromothiophene) (PTBr) over graphene quantum dot (GQD) was noticed. Both the composites had shown quenched photoemission but exhibited a much improved photocurrent generation than the pristine components. However, relatively high concentration of poly (3-bromothiophene) (PTBr) coupled with its stronger interaction with graphene quantum dot (GQD) in the in-situ composite had produced a stronger red shift and much higher photocurrent efficiency than that in the ex-situ sample. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Polysaccharides based ternary semi IPN developed for enhanced adsorption of Pb (II) and Hg (II). • Exclusive network rheology and crystallinity influences faster adsorption of ions. • Adsorption efficiency found analogous to the swelling behavior of adsorbate. An elastic semi IPN from guar gum (GG), xanthan gum (XG) and poly(acrylic acid) (PAA) was developed and used as a bioadsorbent for soluble Pb(II) and Hg(II) from water. The IPNs were developed using a photo-initiated crosslinking cum polymerization approach (benzophenone was used as an initiator) with a variable composition of the biopolymers (GG:XG fixed at 20:80 by mass) to PAA by mass (Biopolymers: PAA as 90:10, 80:20, 70:30 and 50:50, respectively). The hybrids were extensively characterized for microstructure, morphology, swelling, porosity and rheological behavior, both in dry and swelled conditions. Three grades of biosorbents namely 90:10, 80:20 and 70:30 showed an enhanced adsorption efficiency compared to the remaining ternary grades as well as the crosslinked binary grade of GG:XG (20:80 mass composition, used as a control), respectively. It was primarily due to high network strength (elasticity) cum flexibility (more liquid like behavior) of those three ternary grades under swollen condition followed by their higher swelling capacity and strongly negative zeta potential to attract the positively charged Pb(II) and Hg(II), respectively. The 80:20 grade (80 parts was the mass composed of XG:GG in 80:20 mass ratio and 20 parts was the mass of PAA) exhibited the maximum molecular effect and thus recorded the highest adsorption efficiency (93 % for Pb(II) with an adsorption capacity of 111.6 and 72 % of Hg(II) with an adsorption capacity of 86.4). Nevertheless, all the hybrids showed a strong pH dependant adsorption as the –COOH unit present in the network displayed a pH sensitive ionization. The adsorption was lower below the pH level of 4.0 (pKa of PAA at 4.5) while drastically improved beyond that. On additional note, the adsorbate dose was also found to affect the adsorption efficiency whereby a maximum dose of 300 ppm of both Pb(II) and Hg(II) was found to be most effective for adsorption. [ABSTRACT FROM AUTHOR]

In this article distribution of nanoclay between the two phases of a new class of dynamically vulcanized TPV based on POE/EVA(Polyethylene octene elastomer/ethylene vinyl acetate copolymer) elastomers prepared with various amounts of organoclay (0.5, 1 and 3 wt%) using dicumyl peroxide (DCP) as vulcanizing agent by reactive melt blending process has been studied. Different specimens of POE and POE/EVA blend with and without clay were prepared. The effects of organoclay on mechanical properties, swelling kinetics, crystallinity, vulcanization characteristics, dynamic mechanical behaviour, electrical properties and morphology were studied. DMA and morphological analysis revealed the formation of a Thermoplastic vulcanizate. XRD analysis showed decrease in crystallinity on addition of EVA in POE matrix. However, morphological observation of the fractured surface suggested that the smaller EVA domain was quite uniformly distributed into the POE phase and the clay phase was predominantly dispersed in the EVA phase of the TPVs and 0.5% clay mainly improved the mechanical properties and elongation of the blends. Swelling characteristics, electrical properties and storage modulus were also improved with the clay in case of the blend containing higher EVA content which further supports the fact that nanoclay was preferably distributed in the more polar EVA phase. • Nanoclay distribution study in a novel TPV with polar-nonpolar matrix. • Clay shows greater affinity towards the polar component. • Clay distribution identified through dynamic mechanical testing. • Compliance received from morphology and mechanical properties. • Solvent resistance markedly improved through relative distribution of nanoclay. [ABSTRACT FROM AUTHOR]

The present work focuses on the design of a CO 2 scavenger, capable of adsorbing a low concentration of CO 2 from a mixed gas composition. Typically, vinyl imidazole and an ionic liquid brancher were copolymerized by "Strathclyde methodology" and grafted from graphene oxide; GO-g-(HB) PVIm-co-PIL (Cl). The chain transfer agent maintained short chains and developed hyperbranched architecture in GO-g-(HB) PVIm-co-PIL (Cl). The structure and the properties of GO-g-(HB) PVIm-co-PIL (Cl) was established from FTIR, 1HNMR, Raman, XRD and rheology. A metathesis reaction was carried out to exchange chloride anions with hexafluorophosphate anions; GO-g-(HB) PVIm-co-PIL (PF 6). GO-g-(HB) PVIm-co-PIL (PF 6) selectively captured a low concentration of CO 2 from a mixed gas. The surface functionalities/ properties of GO, hyperbranched architecture, porosity, nitrogen content and surface charge distribution together played a significant role in efficient and selective CO 2 capture. • Design of a hybrid material of graphene oxide and hyperbranched polymer grafts. • Metathesis reaction was carried out to exchange anions. • Hybrid materials proved to be efficient in selective CO 2 scavenging. • Hybrid materials detected very low concentration of CO 2. [ABSTRACT FROM AUTHOR]

• Design of a hybrid material of guargum and hyperbranched polymer by grafting. • Hybrid material proved to be an efficient water-absorbing polymer. • Hybrid material served as a gelling agent for the culture of cyanobacteria. • Hybrid material served as an effective medium for plant growth. This study reports the synthesis of an unprecedented bio-based aquasorbent guargum-g-hyperbranched poly (acrylic acid); bGG-g-HBPAA by employing graft-copolymerization and "Strathclyde methodology" simultaneously in emulsion and its possible use as a sustainable nutrient bed for the effective growth of Anabaena cylindrica and Vigna radiata seedlings. The formation of bGG-g-HBPAA and the presence of hyperbranched architectures was confirmed from XRD, FTIR, 13C NMR, solubility, intrinsic viscosity, BET surface area/ pore size, SEM and rheology analyses. The synthesized grade with a branching percent of 65.4% and a swelling percentage of 13,300% facilitated maximum growth of the cultured species as compared to guargum and its linear graft. Semi synthetic bGG-g-HBPAA culture medium was optically transparent, dried at a controlled rate, held a huge amount of water for growth, provided sufficient space for unhindered growth and featured dimensional stability. [ABSTRACT FROM AUTHOR]

Synthetic hyperbranched polyesters with potential therapeutic properties were synthesized using the bifunctional polyethylene glycol or PEG with different molecular weights, ca., 4000, 6000, and 20,000 g/mol, and the trifunctional trans -aconitic acid or TAA. During polycondensation, a fixed amount of PEG was allowed to react with varying amounts of TAA (1:1 and 1:3) to control the branching extents. It was found that the synthetic polyesters had a considerable yield and were highly water soluble. Spectroscopic data (Fourier transform infrared and 1 H NMR) confirmed the polyester formation; the branching percentages were determined from 1 H NMR spectroscopy which varied from 73% to 22% among the synthesized samples. As the molecular weight of PEG was increased, the branching percentage drastically dropped. All polyesters were found to be negatively charged due to the ionization of unreacted -COOH in the branched ends at the working pH (7.4). Both the hydrodynamic size and intrinsic viscosity were found to reduce as the branching extent increased. Among the sets of polyesters, the one with the highest branching percentage (73%) showed the core-shell morphology (evident from field emission scanning electron microscopy and transmission electron microscopy studies). It also exhibited the highest efficiency toward Ca 2+ influx in neuronal cells due to the unique morphology and the negatively charged surface. Nevertheless, this particular grade of polyester along with all the other grades was cytocompatible and induced reactive oxygen species generation. Since the maximally branched grade was highly efficient in altering the Ca 2+ signaling through stronger influx, it may well be tested for treating neuronal disorders in vivo in future.

Bottlebrush polymers represent an important class of high-density side-chain-grafted polymers traditionally with high molecular weights, in which one or more polymeric side chains are tethered to each repeating unit of a linear polymer backbone, such that these macromolecules look like "bottlebrushes". The arrangement of molecular brushes is determined by side chains located at a distance considerably smaller than their unperturbed dimensions, leading to substantial monomer congestion and entropically unfavorable extension of both the backbone and the side chains. Traditionally, the conformation and physical properties of polymers are influenced by external stimuli such as solvent, temperature, pH, and light. However, a unique stimulus, salt, has recently gained attention as a means to induce shape changes in these molecular brushes. While the stimulus has been less researched to date, we see that these systems, when stimulated with salts, have the potential to be used in various engineering applications. This potential stems from the unique properties and behaviors these systems show when exposed to different salts, which could lead to new solutions and improvements in engineering processes, thus serving as the primary motivation for this narrative, as we aim to explore and highlight the various ways these systems can be utilized and the benefits they could bring to the field of engineering. This Review aims to introduce the concept of stimuli-responsive bottlebrush polymers, explore the evolutionary trajectory, delve into current trends in salt-responsive bottlebrush polymers, and elucidate how these polymers are addressing a variety of engineering challenges., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Objective: The current systematic and meta-static review aimed to analyze the correlation between isolated gastrocnemius contracture and plantar fasciitis and the effectiveness of gastroc recession surgery in the treatment of plantar fasciitis., Methodology: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to conduct this meta-analysis. A literature search was carried out on the following databases, including Google Scholar, PubMed, EMBASE, and the Cochrane databases with the appropriate medical subject headings (MeSH) to identify the eligible articles., Results: A total of 13 studies were included in this meta-analysis. In this study, there is a significant difference in chronic plantar fasciitis outcome when comparing experimental and control (RR: 0.02; 95% CI: 0.01 to 0.05; P <  0.001; I 2  = 29%). There is a significant difference in pain scale outcome when comparing pre-treatment and post-treatment (RR: 3.25; 95% CI 1.44 to 7.32; P =  0.004 < 0.01; I 2  = 0%). A significant difference in VAS scale outcome when comparing pre-treatment and post-treatment (RR: 2.58; 95% CI 1.52 to 4.38; P =  0.0004 < 0.01; I 2  = 0%)., Conclusion: In conclusion, the current systematic review and meta-analysis of gastrocnemius recession and proximal medial gastrocnemius release and other treatment measures for plantar fasciitis suggests that the improvement of ankle dorsiflexion, reduction in pain, and patient satisfaction are almost similar in all the treatment measures. Among the five treatment measures, gastrocnemius recession remains the best, followed by proximal medial gastrocnemius release., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Indian Orthopaedics Association 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Background: Calcaneal fractures are serious injuries that mainly affect young, active people. As a result, these fractures may cause long-term impairment and have a major socioeconomic impact. The current updated systematic review and meta-analysis were conducted to evaluate the functional outcomes, re-operative risk, and complications associated with the treatment of displaced intra-articular calcaneal., Methodology: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed to conduct this meta-analysis. The literature search was carried out using PubMed, Cochrane, MEDLINE, Google Scholar, and the EMBASE databases with the appropriate keywords., Results: A total of 13 studies were included in this review. The follow-up months were diverse, ranging between 12 and 65 months in sinus tarsi approach (STA) and 12 to 76 months in extended lateral approach (ELA) methods. Time to surgery was shorter for the STA when compared to ELA (MD: 3.48; 95% CI 2.43 to 4.53; p  < 0.00001). No significant difference was observed in functional outcomes between STA and ELA (MD: 0.34; 95% CI: -0.37 to 1.04; p  = 0.35 > 0.05; I 2  = 88%). In comparison to the ELA, the STA has significantly less wound healing complications (RR: 0.20; 95% CI 0.11 to 0.36; p 0.00001; I 2  = 0%)., Conclusion: In conclusion, the STA technique in treating calcaneal fractures was significantly safer and more effective when compared to the ELA methods. The STA method of treatment was found to have a lower risk of complications and an infection rate, as well as a shorter operating and recovery time., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© Indian Orthopaedics Association 2023, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Trimesic acid (TMA) and ethyelene diamine (ED) were reacted in various molar proportions to yield several branched/hyperbranched copolymers which formed polymersome-like structures, and they were used for encapsulation and release of a model drug, α-tocopherol succinate (TOS). The branched topology of the copolymers was established from spectroscopy, viscometry, and rheological measurements. Hydrodynamic size and transmission electron microscopy revealed the self-aggregated polymersome-like features of the copolymers with a dense core. Zeta potential studies unveiled pH-sensitive features of the aggregates. Both hydrodynamic size and viscosity were found to decrease with more branching, whereas the encapsulation efficiency displayed a drastic increase from 68 to 89.5% from the least branched (30%) to mostly branched grade (68%). The hydrophobic drug was primarily accommodated within the macromolecular voids inside the core and was released slowly following the diffusion mechanism. An indigenous model was established to explain the release kinetics from such a pH-sensitive and highly branched core-shell matrix which yielded a unique parameter called effective diffusivity or ED that took account of those parameters affecting the release rate. The copolymers were found to be biologically viable through a series of in vitro tests, thus inviting in vivo trials for future experimentation.

A biosorbent for adsorption of soluble, inorganic Pb(II) was prepared through a photocrosslinking of a mixture of xanthan gum and guar gum at various mass ratios. The polysaccharide mixes were irradiated using UV A in presence of benzophenone. Chemical crosslinks were formed which led to a controlled swelling of the polysaccharide mix (swelling ratio <20%), referred as crosslinked hybrid in the text. The hybrids were characterized for microstructure, rheology, surface area and surface charge behavior. Interesting changes in crystallographic pattern, both in the pre and the post adsorption stages, was investigated using x-ray diffraction technique. Adsorption efficiency was estimated in respect of blend composition, adsorbate-adsorbent concentration and pH under competitive and non-competitive conditions. A correlation between the swelling of the crosslinked hybrid and the metal adsorption was drawn at various pH to elucidate an interaction between the two phenomena., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Noble copolymers from xanthan gum (XG) and poly(acrylic acid) (PAA) were synthesised through surfactant mediated graft copolymerization. The copolymers were applied as a biosorbent for inorganic Hg(II) at higher concentration level (300ppm). The copolymers were characterized using different analytical techniques which showed, the grafting principally occurred across the amorphous region of XG. Measurement of zeta potential and hydrodynamic size indicated, the copolymers were strong polyanion and possessed greater hydrodynamic size (almost in all cases) than XG, despite a strong molecular degradation that took place simultaneously during grafting. In the dispersed form, all grades of the copolymer displayed higher adsorption capability than XG, however, the grade with maximum grafting produced the highest efficiency (68.03%). Manipulation produced further improvement in efficiency to 72.17% with the same copolymer after 75min at a pH of 5.0. The allowable biosorbent dose, however, was 1000ppm as determined from the experimental evidences., (Copyright © 2016. Published by Elsevier Ltd.)

This is probably the first report on kaolin flocculation done with aqueous guar gum (GG) at various pH. Dynamic light scattering and reduced viscosity proved the polyelectrolytic feature (zeta potential) of aqueous GG which changed on changing pH. Interestingly, the molecular size of GG did not always increased with rising zeta potential due to strong intermolecular repulsion leading to macromolecular recoiling. Best pH range for settling was 4.0-5.0 which included isoelectric point (IEP) of kaolin. Post-settling turbidity was also acceptable at that range. Optimized GG was further blended with oligomeric poly (vinyl alcohol) (PVA) (Mn 14,000) to prepare a new set of flocculant. Oligomeric PVA was previously optimized at similar pH as excellent kaolin flocculant in our earlier investigation. All GG-PVA blends including neat GG exhibited faster settling than neat PVA. However, settling times of all blend compositions were slightly greater than that of neat GG except for few cases where the post settling turbidity was found significantly lower than all our previous investigations., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A promising method of micropropagation of Stevia rebaudiana Bertoni has been developed with an aim to increase the biomass, survivability of the plantlets and stevioside production, using chlorocholine chloride (CCC). Microshoots transferred to the MS medium containing different combinations CCC and IBA were found to be most effective in terms of growth pattern, hardening ability of the plantlets and stevioside content, compared to MS medium containing either IBA or CCC. Among other combinations tested, MS medium supplemented with 3 mg/l CCC and 3 mg/l IBA was found most effective in inducing significant changes like reduced shoot length, increased number of roots, higher leaf size, increased biomass and chlorophyll retaining capacity, higher survival percentage and most importantly the elevated stevioside content. Collectively, the major observations of this research indicate that application of CCC in micropropagation of S. rebaudiana Bertoni is a promising approach and has commercial prospects., (Copyright © 2012 Académie des sciences. Published by Elsevier SAS. All rights reserved.)

To determine the prevalence of dry eye diseases in general clinical ophthalmic practice in a hospital-based population in West Bengal, Eastern India, a cross-sectional study was undertaken among 3023 subjects with the age of > or = 30 years, attending general ophthalmic clinic in a tertiary eye hospital. Demographics, detailed history and 6-items McMonnies' dry eye questionnaire were asked. Tear film break-up time (TBUT), Schirmer-I test, Rose Bengal (RB) staining, slit lamp examination and Meibomian gland dysfunction (MGD) were studied. Dry eye diseases were significantly higher in women than in men ie, 51.9% versus 48.1% (p < 0.01). Symptom-based dry eye (one or more symptoms present often or most of the time) was diagnosed in 1234 subjects (40.8%). With symptoms and at least one sign [TBUT < 10 seconds, RB staining (van Bjisterveld score: 4 or more) and Schirmer-I test = 5 mm in 5 minutes], the prevalence of dry eye was 786 (26%). Different grades of MeibOmian gland dysfunction (MGD) were detected in 957 cases (31.7%). Primary Sjogren syndrome was found in 21.5%; and 10.9% patients of dry eye had some form of systemic collagen vascular disorders. Using computers was not a risk factor in this geographical area. No significant correlation was seen between significant symptoms and positive signs in the study population. The prevalence of dry eye disease is high in West Bengal, Eastern India in hospital-based population. The risk is higher with age, female gender, systemic collagen diseases and with oral antidepressant/anxiolytic medication. Meibomian gland dysfunction is found to be common among dry eye subjects.

Chylous pericardial effusion is an uncommon condition, and the treatment is difficult. We report a case of massive chylous pericardial effusion with tamponade in a 22-year-old man, managed successfully. Lymphoscintigraphy confirmed the communication between the lymphatic trunk and the pericardial space, which was surgically ligated. There are relatively few published reports of idiopathic chylopericardium, and its pathogenesis remains unknown. The most effective treatment is surgical ligation of the thoracic duct and creation of a pericardial window.