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Polyvinyl alcohol (PVA) is a widely used polymer that is biocompatible, nontoxic, and water-soluble due to the presence of hydroxyl groups in its domain. This study aims to investigate the effects of fumaric acid (FA) cross-linking and thermal cross-linking (TC) on the PVA's mechanical and thermal properties. When the FA is mixed with PVA, it was found in the chemical reaction that the OH groups of PVA are condensing with the carboxylic acid units of FA to yield new ester linkages and water as a by-product, which further results in the reduction of the water absorption capacity. Quantitatively, the addition of 8 (wt. /wt. %) FA resulted in a minimum of 65% water absorption rate, as compared with 117% for pure PVA. The mechanical and thermal properties of PVA also enhanced with the addition of 2% to 8% FA by weight. For the TC case, the % increase in ultimate tensile strength was 30.9% and 42.5% with and without TC, respectively. As the wt. % of FA increased from 2 to 10%, the % elongation value decreased for both with and without TC films relative to pure PVA. The thermogravimetric analysis revealed the change in degradation temperature of FA-PVA blended film in comparison with pure PVA. Dynamic mechanical analysis was utilized to analyze the viscoelastic nature and temperature variation at the glass transition temperature. The current fabricated film is a potential candidate for the food packaging films application; moreover, the results reported in this investigation will accelerate the industrial applications of biodegradable PVA. Highlights * Increasing the weight percentage of fumaric acid leads to an enhancement in mechanical and thermal properties of the film. * Esterification is the usual reaction between fumaric acid and polyvinyl alcohol (PVA), in which ester linkages are formed when the carboxyl groups (-COOH) of fumaric acid and the hydroxyl groups (-OH) of PVA combine. * Water absorption characteristics of the film reduces as the wt. % of fumaric acid increases. * Thermal cross-linking of the film leads to further improvements in mechanical and thermal properties. * The overall effect of increasing the wt. % of fumaric acid is negative on the glass transition temperature of the film. * The developed film is a potential candidate for the food packaging films application. KEYWORDS biodegradable polymers, cross-linking, fumaric acid, mechanical and thermal properties, polyvinyl alcohol, 1 | INTRODUCTION Polyvinyl alcohol (PVA) owing to its biocompatibility, biodegradability, and moderate mechanical properties has gained worldwide attention as one of the most important synthetic biodegradable polymers for the [...]

An efficient catalytic system employing TMS•OTf for the regioselective thiolation of electron‐rich arenes with sulfonyl hydrazides has been developed. The reaction occurs in a solvent mixture of dichloroethane and trifluoroethanol under mild conditions, with the addition of water. This method furnishes a range of para‐thio‐substituted arenes and 3‐sulfenyl‐indoles in good to excellent yields, marking a significant advancement in organic synthesis. [ABSTRACT FROM AUTHOR]

The renin‐angiotensin system (RAS) is crucial for regulating and understanding the pathophysiology of hypertension. However, there has been little focus on the breakdown of the active peptide, angiotensin II (AngII). Given that animals lacking aminopeptidase A (APA) exhibit hypertension, it may be concluded that APA is a crucial enzyme in regulating blood pressure by breaking down AngII. It has been also seen that the elevated blood pressure in the spontaneously hypertensive rat (SHR) is caused by the activation of the RAS and a concurrent reduction in renal angiotensin‐converting enzyme (ACE) activity. The activity of APA is elevated at the beginning of pre‐eclampsia and decreases below the levels seen during a normal pregnancy as pre‐eclampsia progresses (particularly, in severe cases). The activity of Serum APA is also heightened after hormone replacement treatment (HRT), perhaps as a response to increasing levels of AngII. Therefore, it is crucial to examine the connection between the activation of the RAS, the levels of AngII in the bloodstream, and the presence of APA in hypertension conditions. Summary: Aminopeptidase A (APA) plays a critical role in the regulation of blood pressure by modulating the renin‐angiotensin system. Inhibiting APA offers a novel therapeutic approach to reducing hypertension, particularly, in cases resistant to conventional treatments. This systematic review highlights the growing evidence supporting APA as a promising target for effective hypertension management. [ABSTRACT FROM AUTHOR]

There is accumulating evidence of the presence of Cancer Stem Cells (CSCs) within meningiomas (MGs). In the present study, we assessed the Immunohistochemistry (IHC) expression of stem cell markers SOX2, OCT4, CD133 in different grades of MGs and their correlation with Ki 67 index. A cross-sectional analytical study where 140 MGs cases were graded and classified according to WHO-2021 classification. IHC for SOX2, OCT4, CD133 and Ki-67 was carried out. Out of 140 cases, 59 cases (42.1%) showed OCT4 positivity, 38 cases (27.1%) showed CD133 positivity and only 21 cases (15%) showed SOX2 positivity. Ki 67 index ranged from 1-30%. Statistically significant difference (Chi Square p-value <0.001) was found between SOX 2, OCT4 and CD133 expressions (positive/negative) and the grades of MG cases. As the grades of MG cases increased, the positive expression of SOX2, OCT 4 and CD 133 also increased. The Mean Ki 67 index value was significantly raised when SOX2, OCT 4 and CD 133 IHC expressions were positive (Student t Test p-value <0.001). Our results strongly support the hypothesis of presence of CSCs, in MGs regardless of their grade. We recommend that CSCs IHC markers (SOX2, OCT4 and CD133) to be used on initial diagnosis in all cases of MGs along with Ki-67 index. It can help quantitate CSCs and in turn, recommend closer follow up in patients with high percentage of CSCs to predict early recurrence. [ABSTRACT FROM AUTHOR]

Cricula trifenestrata Helfer (commonly known as Amphutukoni muga/Cricula silkworm), a wild sericigenous insect produces golden yellow silk similar to Antheraea assamensis (muga silkworm), with significant potential as a natural fiber and biomaterial. Cricula is considered as a pest as it competes for food with muga, which produces the prized golden silk. This study focuses on decoding the mitochondrial genome of C. trifenestrata using next-generation sequencing technology and includes comparative analysis with Bombycoids and other lepidopteran insects. We found that the Cricula mitogenome spans 15 425 bp and exhibits typical gene content and arrangement consistent with other Saturniids and lepidopterans. All protein-coding genes were found to undergo purifying selection, with the highest and lowest conservation observed in the cox1 and atp8 gene, respectively, indicating their potential role in future evolutionary events. We identified two types of mismatches: 23 "G–U" and 6 "U–U" pairs, similar to those found in Actias selene among the Saturniids. Additionally, our study uncovered the presence of two 33 bp repeat units and a "TTAGA" motif in the control region, in contrast to the typical "ATAGA" motif, suggesting functional similarity with evolving sequences. Furthermore, phylogenetic analysis supports the close relationship of Cricula with other species within the Saturniidae family. [ABSTRACT FROM AUTHOR]

The high specific surface area of graphene is an important factor to enable a large molecular adsorption on the surface, thus enabling direct sensing on a versatile surface. A large area graphene sensor (1 cm2) is fabricated using a transfer method for the detection of ammonia (NH3) gas under ambient conditions. The ambient atmosphere contains 21% oxygen (O2), and thus it is crucial to understand its impact on the sensing of ammonia gas. The sensing response is analyzed under both the inert nitrogen (N2) gas and condensed dry air (CDA) containing 78.08% N2, 20.95% of O2, and 0.93% of argon gas. Upon interaction with the graphene, both NH3 and O2 resulted in opposite electrical responses. Thus, this finding reveals a polarity dependent interaction of gases with the graphene. [ABSTRACT FROM AUTHOR]

Photo-rechargeable supercapacitors serve as a bridge between batteries and solar cells for developing efficient energy storage devices. Unlike previous studies where there was either (a) a heterostructure of zinc oxide (ZnO) with other electroactive materials or (b) a coating of ZnO powder on the current collector, here, ZnO nanorods grown on fluorine-doped tin oxide (FTO) were used as photoelectrodes. Our devices tested with (i) an ionic liquid electrolyte and (ii) a gel electrolyte exhibited a capacitance rise of ∼3006% (>10× the previous record) and ∼500% (2× the previous record) compared to that under dark conditions, which is attributed to the electrode synthesis technique adopted in this study. A higher ionic diffusivity in the ionic liquid electrolyte leads to a higher capacitance rise. Notably, a novel necking behavior (a possibly higher incremental capacitance at higher voltages) was observed during galvanostatic charge/discharge tests under UV illumination for both electrolytes, which is attributed to the high electrode porosity. Contrary to conventional wisdom, higher capacitance was recorded at higher current densities during galvanostatic charge/discharge tests under UV illumination for ionic liquid-based supercapacitor cells. A first-ever physics-based continuum scale model for photo-rechargeable supercapacitors is proposed to explain the above intriguing experimental observations, paving a path for the design of fast-charging high-capacitance supercapacitors. [ABSTRACT FROM AUTHOR]

Introduction: Phosphatidylethanol (PEth) is a long‐term marker of alcohol consumption used frequently in clinical scenarios such as liver transplant evaluation. Recent cases have demonstrated that packed red blood cell (pRBC) transfusion creates the potential for artificial elevation or decrease of observed PEth concentrations in recipients. Very little is known about the prevalence or stability of PEth in pRBCs. Methods: Apheresis and whole‐blood (WB) donations were tested for PEth using liquid chromatography – tandem mass spectrometry with limit of quantitation 10 ng/mL. Units were stored under routine blood bank conditions to evaluate the stability of PEth and the impact of irradiation. Results: Over 40% of apheresis and WB donors had PEth ≥10 ng/mL (maximum observed 587 ng/mL). As WB units were processed into component pRBCs, PEth concentrations increased and were higher than donor WB levels (EDTA sample) prior to collection (maximum observed 711 ng/mL). Storage for up to 5 weeks post donation resulted in mean 17.3% decrease in PEth‐positive units; in contrast to a prior report, we observed no PEth formation in units with negative (<10 ng/mL) baseline concentrations. Irradiation of pRBCs did not substantially affect PEth concentrations in either PEth‐positive or PEth‐negative units. Discussion: PEth concentrations in healthy blood donors may potentially confound alcohol use or abstinence assessment in pRBC recipients. Transfusion medicine services and clinical practices such as transplantation and behavioral medicine should recognize this phenomenon and collaborate on testing protocols to appropriately interpret PEth in pRBC recipients. [ABSTRACT FROM AUTHOR]

In the current investigation, enhancement in the mechanical properties, thermal stability, and decrement in the moisture absorption capabilities of polyvinyl alcohol was observed by cross‐linking it with different weight percentages (wt. %) of fumaric acid and reinforcing them along with sulfuric acid‐modified graphite particles. The effects of altering the cross‐linking duration and fumaric acid wt. % were investigated in the resulting composite using the Taguchi L16 experimental design method. As in this contemporary era of rapid industrial expansion and fierce competition, the primary goals of manufacturers revolve around the production of high‐quality goods at optimal costs within a specified timeframe. Therefore, to save both cost and time, the authors have utilized a technique known as "gray‐fuzzy optimization" to balance competing goals between mechanical (toughness, elongation and strength) and physical (water intake capacity) attributes. The present approach aimed to reduce the experimentation expenses and increase the effectiveness of composite manufacturing by considerably reducing the intricacy of practical multi‐response optimization issues. Response graphs and analysis of variance tests were also utilized to calculate the percentage contribution of the input variables and provide model significance. Highlights: Polyvinyl alcohol is cross‐linked with different weight percentages (wt. %) of fumaric acid, and reinforced them with sulfuric acid‐modified graphite particles.Enhancement in mechanical properties, thermal stability, and decrease in moisture absorption capabilities were perceived for the fabricated composite.Effects of altering the cross‐linking duration and fumaric acid wt. % were investigated in the resulting composite using the Taguchi L16 experimental design.Gray‐fuzzy optimization technique was utilized to balance competing goals between water intake and mechanical attributes like toughness, elongation and strength.Response graphs and analysis of variance (ANOVA) tests were also utilized to evaluate the percentage contribution of input variables and provide model significance. [ABSTRACT FROM AUTHOR]

Many environmental features are cyclic, with predictable changes across the day, seasons and latitudes. Additionally, anthropogenic, artificial-light-induced changes in photoperiod or shiftwork-driven novel light/dark cycles also occur. Endogenous timekeepers or circadian clocks help organisms cope with such changes. The remarkable plasticity of clocks is evident in the waveforms of behavioural and molecular rhythms they govern. Despite detailed mechanistic insights into the functioning of the circadian clock, practical means to manipulate activity waveform are lacking. Previous studies using a nocturnal rodent model showed that novel light regimes caused locomotor activity to bifurcate such that mice showed two bouts of activity restricted to the dimly lit phases. Here, we explore the generalizability of these findings and leverage the genetic toolkit of Drosophila melanogaster to obtain mechanistic insights into this unique phenomenon. We find that dim scotopic illumination of specific durations induces circadian photoreceptor CRYPTOCHROME-dependent activity bifurcation in male flies. We show circadian reorganization of the pacemaker circuit, wherein the 'evening' neurons regulate the timing of both bouts of activity under novel light regimes. Our findings indicate that such environmental regimes can be exploited to design light cycles, which can ease the circadian waveform into synchronizing with challenging conditions. [ABSTRACT FROM AUTHOR]

Fused pyranochromenone derivatives have extensive applications in medicinal chemistry. Herein, we report the first HFIP/TsOH catalyzed, one-pot domino reaction by cleavage of the C(sp2)–OMe bond. Control experiments reveal that 1,3,5-trimethoxybenzene is rapidly protonated in the presence of HFIP to yield a dearomatized cationic diene intermediate. The gram-scale reaction and late-stage functionalization of natural products justified the practicality of this protocol. [ABSTRACT FROM AUTHOR]

Background: To explore the association of carotid intima medial thickness (CIMT) with TSH and other biochemical parameters among young adults with thyroid dysfunction. Material methods: Our study included 50 young subjects, 13-39 years, attending endocrinology clinic of our centre for thyroid dysfunction with no associated co-morbidities. BMI, thyroid and biochemical profile was assessed for all. All subjects underwent measurement of right and left CIMT using sonography (linear transducer 7mHz frequency). Statistical methods were then used to analyse the data. Results: CIMT values in our 50 subjects [hypothyroid: n=37 and hyperthyroid: n=13; age: 27.6±7.1 years ] fell in the normal range (Rt=0.53± 0.10 mm; Lt=0.52±0.11 mm). Hypothyroids had a significantly higher HbA1C (p value; 0.038) and Serum cholesterol (p value; 0.028) levels as compared to hyperthyroid subjects. When the values for the entire group were studied, CIMT values did not correlate either with TSH or BMI [24.66±4.14 kg/m. sq.]; though it positively correlated with age and HbA1c (particularly right CIMT, correlation coefficient, 0.50). Hyperthyroid subjects had a significant positive correlation of TSH with Rt CIMT(0.750) and S.creatinine (0.780) and a negative correlation with cholesterol (-0.700). On the other hand, in hypothyroids, TSH levels did not significantly correlate with any parameters other than age (-0.38). Conclusion: Higher HbA1c (even in non diabetic range) are associated with higher CIMT among young patients of thyroid dysfunction, making it a useful tool for monitoring cardiovascular risk in conjunction with CIMT, especially in those with hypothyroidism. [ABSTRACT FROM AUTHOR]