Synthesis and characterization of photoplastic siloxane based thiol-ene polymer systems

Photoplasticity is a phenomenon wherein the shape of crosslinked polymers, under stress, can be induced to change by irradiation with light. Photoplasticity in crosslinked polymer systems via stress relaxation has been reported in polyether-acrylate thiol-ene polymer systems by incorporating allyl thioether functionality by ring-opening copolymerization with 6-methyl-3- methylene-1,5-dithiacyclooctane (MDTO). The object of the present work is to adapt the photoplastic stress relaxation approach to demonstrate shape change in silicone elastomers. The apparent way to achieve this is end is to replace the polyether-acrylate thiol-ene monomers, employed in the published literature, with multi-functional silicone-thiols and alkenyl endfunctional siloxanes chain extended with MDTO. While homogeneous amorphous elastomeric siloxane-based thiol-enes are well known, it was found that copolymerization of MDTO with the thiol-ene siloxane monomers leads to formation of stable heterogeneous polymer emulsions. Such behavior of thiol-ene siloxanes in the presence of MDTO was found to be a result of the tendency of MDTO to homopolymerize and incipient immiscibility in solutions of MDTO and functionalized siloxane oligomers. The nature of the emulsion formed and extent of crosslinking can depend on factors such as the reactivity of the alkene, the nature of the thiol component and the type of initiation process used. Given that the ring-opening of MDTO was initiated from the multifunctional siloxane thiol, the degree to which chemically different dialkenyl siloxanes were incorporated in the reaction was investigated. Irrespective of the reactivity of the alkene, homopolymerization of MDTO and formation of heterogeneous emulsions and gels always resulted when either the thiol, the ene or both were derived from siloxane oligomers

Agree To Disagree

How frequently do individuals thoroughly review terms and conditions before proceeding to register for a service, install software, or access a website? The majority of internet users do not engage in this practice. This trend is not surprising, given that terms and conditions typically consist of lengthy documents replete with intricate legal terminology and convoluted sentences. In this paper, we introduce a Machine Learning-powered approach designed to automatically parse and summarize critical information in a user-friendly manner. This technology focuses on distilling the pertinent details that users should contemplate before committing to an agreement

Rectal gel application of Withania somnifera root extract expounds anti-inflammatory and muco-restorative activity in TNBS-induced Inflammatory Bowel Disease

<p>Abstract</p> <p>Background</p> <p>Inflammatory Bowel Disease (IBD) is marked with chronic inflammation of intestinal epithelium driven by oxidative stress. Traditional treatments with plant extracts gained renewed interest due to their ability to ameliorate the multi factorial conditions like inflammation. We investigated the beneficial effects of <it>Withania somnifera </it>in Trinitro Benzyl Sulfonic Acid (TNBS) induced experimental IBD through a rectally applicable formulation.</p> <p>Methods</p> <p>The study included (i) preparation of gel formulation from aqueous <it>Withania somnifera </it>root extract (WSRE), (ii) biochemical assays to determine its performance potential, (iii) testing of formulation efficacy in TNBS-induced IBD rat model, and (iv) histo-patholgical studies to assess its healing and muco-regenerative effect in IBD-induced rats. For this purpose, concentration dependant antioxidant activity of the extracts were evaluated using biochemical assays like (a) inhibition of lipid peroxidation, (b) NO scavenging, (c) H₂O₂scavenging, and (d) ferric reducing power assay.</p> <p>Results</p> <p>The extract, at 500 μg/ml, the highest concentration tested, showed 95.6% inhibition of lipid peroxidation, 14.8% NO scavenging, 81.79% H₂O₂scavenging and a reducing capacity of 0.80. The results were comparable with standard antioxidants, ascorbic acid and curcumin. WSRE treatment positively scored on histopathological parameters like necrosis, edema, neutrophil infiltration. The post treatment intestinal features showed restoration at par with the healthy intestine. In view of these results, gel formulation containing an aqueous extract of <it>W. somnifera</it>, prepared for rectal application was tested for its anti-inflammatory activity in TNBS-induced rat models for IBD. Commercially available anti-inflammatory drug Mesalamine was used as the standard in this assay.</p> <p>Conclusions</p> <p>Dose of the rectal gel applied at 1000 mg of WSRE per kg rat weight showed significant muco-restorative efficacy in the IBD-induced rats, validated by histo-pathological studies.</p

Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed

Dataset to support : Thermal analysis of novel Nitrate-Chloride salt mixtures for CSP applications

Nitrate salts have better thermal stability, low vapour pressure and non-toxic nature compared to synthetic heat transfer oil like Therminol VP-1®. Solar salt, a mixture of 60%NaNO3 -40%KNO3 by weight, is finding increased application as a Heat Transfer Fluid (HTF) and Thermal Energy Storage (TES) material in Concentrated Solar Power (CSP) plant. In this research work, two novel salt mixtures are prepared and tested for their melting point, short and long duration thermal stability. The formulation 1 is a ternary salt comprising of 44%KNO3- 32%Ca(NO3)2- 24%NaNO3, referred to as Base Salt. Formulation 2 is a quinary mixture of 90%Base salt + 5%NaCl + 5%KCl, referred to as Base-Chloride. Solar salt is also tested and compared alongside the novel mixtures. The experiments conclude that the melting point of Solar salt is 223°C, Base salt is 135.8°C and Base-Chloride is 142.2°C. Considering Short duration thermal stability, decomposition point of Solar salt is 631°C, Base salt is 585°C and Base-Chloride is 589°C. Considering long duration stability, all the three mixtures remain stable till 400°C, when heated at constant temperature for 24 hours. The novel mixtures have significantly lower melting points, thus providing wider operating temperature range compared to Solar salt

Thermal analysis of novel Nitrate-Chloride salt mixtures for CSP applications

Nitrate salts have better thermal stability, low vapour pressure and non-toxic nature compared to synthetic heat transfer oil like Therminol VP-1®. Solar salt, a mixture of 60%NaNO3 -40%KNO3 by weight, is finding increased application as a Heat Transfer Fluid (HTF) and Thermal Energy Storage (TES) material in Concentrated Solar Power (CSP) plant. In this research work, two novel salt mixtures are prepared and tested for their melting point, short and long duration thermal stability. The formulation 1 is a ternary salt comprising of 44%KNO3- 32%Ca(NO3)2- 24%NaNO3, referred to as Base Salt. Formulation 2 is a quinary mixture of 90%Base salt + 5%NaCl + 5%KCl, referred to as Base-Chloride. Solar salt is also tested and compared alongside the novel mixtures. The experiments conclude that the melting point of Solar salt is 223°C, Base salt is 135.8°C and Base-Chloride is 142.2°C. Considering Short duration thermal stability, decomposition point of Solar salt is 631°C, Base salt is 585°C and Base-Chloride is 589°C. Considering long duration stability, all the three mixtures remain stable till 400°C, when heated at constant temperature for 24 hours. The novel mixtures have significantly lower melting points, thus providing wider operating temperature range compared to Solar salt

Chemical Modification of Alginates in Organic Solvent Systems

Alginates are (1→4)-linked linear copolysaccharides composed of β-d-mannuronic acid (M) and its C-5 epimer, α-l-guluronic acid (G). Several strategies to synthesize organically modified alginate derivatives have been reported, but almost all chemistries are performed in either aqueous or aqueous–organic media. The ability to react alginates homogeneously in organic solvents would open up access to a wide range of new chemistries and derivatives. However, past attempts have been restricted by the absence of methods for alginate dissolution in organic media. We therefore report a strategy to dissolve tetrabutylammonium (TBA) salts of alginic acid in polar aprotic solvents containing tetrabutylammonium fluoride (TBAF). Acylation of TBA-alginate was performed under homogeneous conditions, such that both M and G residues were acetylated up to a total degree of substitution (DS) ≈1.0. Performing the same reaction under heterogeneous conditions resulted in selective acylation of M residues. Regioselectivity in the acylated alginate products was studied, and degradation under basic reaction conditions was probed

Scanning Electron Microscopy Analysis of the Intratubular Radicular Dentin Penetration of Calcium Hydroxide, Triple Antibiotic Paste, and Nitrofurantoin

The aim of this study is to assess and analyze the intratubular penetration of the intracanal medications nitrofurantoin (Nit), triple antibiotic paste (TAP), and calcium hydroxide (CH). Sixty freshly extracted single-rooted teeth were acquired and decoronated to a standard length of 15 mm. To prepare specimens up to size F3, rotary ProTaper instrumentation was employed. The prepared teeth were divided into three groups, each of which received one of the tested intracanal medicaments: Group I (calcium hydroxide), Group II (triple antibiotic paste), and Group III (nitrofurantoin). Using a size #30 Lentulo spiral, a freshly prepared therapeutic paste was placed into the canals, and the intracanal medicaments were allowed to set in the incubator at 100% humidity. The samples were subsequently sliced perpendicularly to their long axis using a precision saw and assessed under a scanning electron microscope to assess the depth of penetration of intracanal medicaments at the coronal, middle, and apical portions of the root canal dentin. The data were analyzed using one-way ANOVA and Tukey’s post hoc test. The statistical analysis revealed a significant difference between the experimental groups in the quantity and depth of sealer penetration (p p < 0.05). In conclusion, this ongoing investigation indicates that nitrofurantoin penetrated dentinal tubules better than calcium hydroxide or triple antibiotic paste