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This manuscript introduces a pyrene-based Schiff base L by reacting pyrenecarboxaldehyde with 2-aminothiazole in equimolar ratio. The ligand L was characterized by various spectral data and single crystal. The water sensing ability of L was examined in different organic solvents. The weakly emissive L in DMSO showed a fluorescence enhancement upon the addition of water. The water-induced fluorescence enhancement of L was occurred due to the combined effect of aggregation-induced emission (AIE) phenomenon and suppression of photo-induced electron transfer (PET) process. Using L, the water in DMSO can be detected down to 0.50 wt% with a quantification limit of 1.52 wt%. The analytical novelty of the developed sensor L was validated by detecting moisture in a variety of raw food products.
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Corantes Fluorescentes , Água , Água/química , Corantes Fluorescentes/química , Dimetil Sulfóxido , Bases de Schiff/química , Pirenos/químicaRESUMO
The oxime functional group is pivotal in chemistry, finding extensive applications in medical science, catalysis, organic functional group transformations, and the recognition of essential and toxic analytes. While the coordination chemistry of oxime derivatives has been thoroughly explored and several reviews have been published on this topic in reputable journals, a comprehensive review encompassing various aspects such as crystal engineering, cation and anion recognition, as well as coordination chemistry activities, is still in demand. This feature article highlights the diverse applications of oxime derivatives across multiple domains of chemistry, including medicine, agriculture, crystal engineering, coordination chemistry, and molecular recognition studies. Each of the oxime derivatives in this feature article are meticulously described in terms of their medicinal applications, crop protection, crystal engineering attributes, analyte recognition capabilities, and coordination chemistry aspects. By providing a comprehensive overview of their versatile applications, this article aims to inspire researchers to explore and develop novel oxime-based derivatives for future applications.
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Background: Increasing stroke burden in India demands a long-term stroke surveillance framework. Earlier studies in India were urban-based, short term and provided limited data on stroke incidence and its outcomes. This gap is addressed by the establishment of five population-based stroke registries (PBSRs) of the National Stroke Registry Programme, India. This paper describes stroke incidence, mortality and age, sex, and subtypes distribution in the five PBSRs with urban and rural populations. Methods: First-ever incident stroke patients in age group ≥18 years, resident for at least one year in the defined geographic area, identified from health facilities were registered. Death records with stroke as the cause of death from the Civil Registration System (CRS) were included. Transient ischemic attack (TIA) was excluded. Three PBSRs (Cuttack, Tirunelveli, Cachar) included urban and rural populations. PBSRs in Kota and Varanasi were urban areas. The crude and age-standardized incidence rate (ASR) by age, sex, and residence (urban and rural), rate ratios of ASR, case fatality proportions and rates at day 28 after onset of stroke were calculated for years 2018-2019. Findings: A total of 13,820 registered first-ever stroke cases that included 985 death certificate-only cases (DCOs) were analysed. The pooled crude incidence rate was 138.1 per 100,000 population with an age-standardized incidence rate (ASR) of 103.4 (both sexes), 125.7 (males) and 80.8 (females). The risk of stroke among rural residents was one in seven (Cuttack), one in nine (Tirunelveli), and one in 15 (Cachar). Ischemic stroke was the most common type in all PBSRs. Age-standardized case fatality rates (ASCFR) per 100,000 population for pooled PBSRs was 30.0 (males) and 18.8 (females), and the rate ratio (M/F) ranged from 1.2 (Cuttack) to 2.0 (Cachar). Interpretation: Population-based registries have provided a comprehensive stroke surveillance platform to measure stroke burden and outcomes by age, sex, residence and subtype across India. The rural-urban pattern of stroke incidence and mortality shall guide health policy and programme planning to strengthen stroke prevention and treatment measures in India. Funding: The National Stroke Registry Programme is funded through the intramural funding of the Indian Council of Medical Research, Department of Health Research, Ministry of Health and Family Welfare, India.
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Heavy metals act as cofactors for several microbial enzymes and are required in low concentrations for the proper biological functioning of yeasts. Because concentrations beyond the permitted threshold can damage a cell's functionality and viability, metal tolerance in yeasts towards such heavy metals is therefore desirable during fermentation. Tyrosol, a quorum-sensing molecule in yeasts, protects yeasts from oxidative stress induced by various factors, but the performance of the molecule under heavy metal-induced stress is not known. In this investigation, the metal tolerance of four species of endemic yeasts from northeast India, Wickerhamomyces anomalus, Candida tropicalis, Saccharomyces cerevisiae and Candida glabrata, isolated from traditional starter culture cakes, was tested towards zinc (Zn+2), manganese (Mn+2), cobalt (Co+2) and copper (Cu+2) in the presence and absence of tyrosols retrieved from these isolates. The decreasing order of the tolerance of isolates was found to be Mn+2 > Zn+2 > Co+2 > Cu+2. Under the influence of tyrosols, isolates showed enhanced growth at their upper metal tolerance limit. Candida tropicalis showed enhanced growth (2-48-fold, P < 0.0001) in all the tested metal consisting medium (2 mM Zn+2, 5 mM Mn+2, 2 mM Co+2 and 1 mM Cu+2), while W. anomalus, C. glabrata and S. cerevisiae showed increased growth (3-17-fold, P < 0.0001) in Zn+2 (2 mM), Mn+2 (5 mM) and Cu+2 (1 mM) augmented medium. The overall result suggests that tyrosol exerts a protective effect under heavy metal-induced stress, which could be useful in enhancing the quality of fermented products.
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Metais Pesados , Álcool Feniletílico/análogos & derivados , Cobre/farmacologia , Metais Pesados/toxicidade , Álcool Feniletílico/isolamento & purificação , Álcool Feniletílico/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Leveduras/efeitos dos fármacos , Leveduras/crescimento & desenvolvimento , Zinco/toxicidadeRESUMO
A strategy for combining metal oxides and metal-organic frameworks is proposed to design new materials for sensing volatile organic compounds, for the first time. The prepared ZnO@ZIF-CoZn core-sheath nanowire arrays show greatly enhanced performance not only on its selectivity but also on its response, recovery behavior, and working temperature.
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A series of linear coordination polymers, metallacycles of cadmium(II) and mercury(II) of flexible carboxylic acid ligands, RCH{3-CH(3)-,5-CH(3)-,6-(-OCH(2)CO(2)H)C(6)H(2)}(2), (when R = C(6)H(5), (H(2)L(1)); 2-NO(2)C(6)H(4)- (H(2)L(2)) and 3-NO(2)C(6)H(4)- (H(2)L(3))) are synthesized and characterized. [CdL(1) (py)(3)](n)·3nH(2)O (py = pyridine) is a linear coordination polymer, whereas [CdL(2)(py)(CH(3)OH)](2)·CH(3)OH is a dinuclear complex of cadmium with a Cd(2)O(2) type of core. The latter is obtained from reaction of cadmium(II) acetate with H(2)L(2) in methanol followed by reaction with pyridine. A similar reaction of cadmium(II) acetate with H(2)L(2) in dimethylformamide results in the formation of a cadmium metallacycle, namely [CdL(2) (py)(2)(H(2)O)](2)·H(2)O. The H(2)L(3) reacted with cadmium(II) acetate in the presence of pyridine to form a metallacycle [CdL(3)(py)(2)(H(2)O)](2)·3H(2)O. The ligand H(2)L(2) form mercury(II) metallacycle [HgL(2)(4-mepy)(2)](2) in the presence of 4-methylpyridine (4-mepy) and the ligand H(2)L(3) forms metallacycle [HgL(3)(3-mepy)(2)](2)·DMF in the presence of 3-methylpyridine (3-mepy). The potassium salts of H(2)L(1) and H(2)L(2) were found to be coordination polymers and these potassium coordination polymers were structurally characterized.
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The UV-visible and fluorescence properties of hydroxy substituted benzothiazole derivatives change on interactions with zinc(II), cadmium(II) and mercury(II) ions. The binding of 2-(2'-hydroxyphenyl)benzothiazole is specific to zinc(II) over cadmium(II) and mercury(II). Similar type of interactions of zinc(II), cadmium(II) and mercury(II) with 2-(2',3',4'-trihydroxyphenyl)benzothiazole is observed in their UV-visible absorptions, whereas 2-(4'-hydroxyphenyl)benzothiazole shows interactions with mercury(II) over the other two ions.