Enhanced triplet state yields in aqueous media of asymmetric zinc phthalocyanines when conjugated to silver nanoflowers

Novel low symmetry water-soluble zinc phthalocyanines (ZnPcs, complexes 1 and 2) were synthesized and then mixed with silver nanoflowers. Photophysical and photochemical studies were performed in order to determine the efficiency of complexes 1 and 2 as photosensitizers when alone and when combined with the silver nanoflowers. The Pcs show low fluorescence quantum yields and excellent triplet quantum yields of 0.78 (for 1) and 0.66 (for 2) in aqueous media. The triplet quantum yield values increased to 0.80 and 0.89, respectively, in the presence of silver nanoflowers. Long triplet lifetimes ranging from 180 to 200 μs in DMSO were obtained for complexes 1, 2 and their conjugates with silver nanoflowers

Synthesis, Photophysical and Photochemical Properties of Poly (oxyethylene)‐Substituted Phthalocyaninato Oxotitanium (IV) Complexes

The synthesis, photophysical and photochemical properties of tetra- and chlorotetrapoly(oxyethylene)-substituted oxotitanium(IV) phthalocyanines are reported for the first time. The new compounds were characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, electronic spectroscopy and mass spectra. These complexes showed monomeric behaviour in solution. General trends are described for photodegredation, singlet oxygen, triplet state and fluorescence quantum yields, and triplet and fluorescence lifetimes of these compounds in dimethyl sulfoxide (DMSO). Photophysical and photochemical properties of phthalocyanine complexes are very useful for PDT applications. The complexes showed high triplet quantum yields and triplet lifetimes in DMSO. The singlet oxygen quantum yields (ΦΔ), which give an indication of the potential of the complexes as photosensitizers in applications where singlet oxygen is required (Type II mechanism), were 0.72 and 0.78 for 3a and 5a, respectively. Thus, these complexes show potential as Type II photosensitizers. These complexes were also quenched by benzoquinone for fluorescence quenching studies

Synthesis and photodynamic potential of tetra-and octa-triethyleneoxysulfonyl substituted zinc phthalocyanines

Synthesis of the water soluble zinc phthalocyanines (3, 4) obtained from the phthalonitriles substituted with oligo(ethyleneoxy)thia groups are described. The new compounds have been characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy, including HSQC, HMBC and COSY bidimensional correlation techniques, electronic spectroscopy and mass spectra. The aggregation behaviour of the phthalocyanine compounds (3, 4) was investigated using UV–vis spectroscopy in dimethylsulphoxide. Photochemical and photophysical measurements were conducted on oligo(ethyleneoxy)thia appended zinc phthalocyanines. General trends are described for quantum yields of photodegredation, fluorescence yields, triplet lifetimes and triplet quantum yields as well as singlet oxygen quantum yields of these compounds. The phototoxicity against cancer cells of the new compounds was investigated during several in vitro experiments. The dye-sensitized photooxidation of 1,3-diphenylisobenzofurane via 1O2 was studied in dimethylsulphoxide

Synthesis, characterization and photophysical properties of cyclotriphosphazenes including heterocyclic rings

In the present work, new cyclotriphosphazene derivatives, {[N3P3(biph)(R)(4)] (biph = 2',2''-dioxy-1',1''-bi-phenyl, R = imidazolyl (5) and benzimidazolyl (7)}, were synthesized for the first time. Both of these compounds (5 and 7) were fully characterized by elemental analysis, mass spectrometry and H-1 and P-31 NMR spectroscopy. The crystal structures of compounds 5 and 7 were determined by single-crystal X-ray crystallography. Furthermore, a second polymorph (triclinic form) of 2,2-monospiro-(2',2''-dioxy-1',1''-biphenyl)-4,4,6,6-tetrachlorocyclotriphosphazene (3) was isolated during the course of our study. UV-Vis absorption and fluorescence emission properties of 3, 5 and 7 were determined in a range of different solvents

Minor cereals exhibit superior antioxidant effects on human epithelial cells compared to common wheat cultivars

In the present study, various minor cereals including rye, oat, spelt, primitive and wild wheat species (20 genotypes each) were tested for their antioxidative effects in cell biological studies, and the effects were compared with the effects of 12 common wheat genotypes. Ethanol soluble extracts of grains were used and studied in human cancer-derived cell lines including HeLa (cervical) and HCT116 (colorectal) cell lines by analyzing cellular levels of reactive oxygen species (ROS), mitochondrial health, DNA damage and cell survival. The cereal genotypes were also examined for the total phenolic concentration (TPC) and for the relationship between oxidative cell damage and TPC values. Most genotypes of the minor cereal species showed superior antioxidant effects in human cell cultures compared to the common wheat genotypes. Many of the minor cereal genotypes with high antioxidant capacities protected DNA and mitochondrial damage and prevented cell death in HeLa cells and colon-derived HCT116 human epithelial cells. There was no significant relationship between TPC values and oxidative cell damage. However, common wheat genotypes had, on average, lower TPC values. The results show that minor cereals contain potentially high levels of certain antioxidant substances which might be useful in preventing oxidative damage in cellular systems

New mixed-ligand iron(III) complexes containing thiocarbohydrazones: Preparation, characterization, and chemical reactivity analysis through theoretical calculations

Five new mixed ligand Fe(III) complexes, namely, [FeL1(acac)] (L1Fe), [FeL2(acac)] (L2Fe), [FeL3(acac)] (L3Fe), [FeL4(acac)] (L4Fe), and [FeL5(acac)] (L5Fe), were synthesized from the reaction of iron(III) acetylacetonate with [ONS] donor dibasic tridentate symmetrical bisthiocarbohydrazone ligands. Synthesized mixed ligand Fe(III) complexes were characterized with infrared spectra, UV-Vis spectra, mass spectra, elemental analysis, magnetic susceptibility measurements, and thermogravimetric analysis. The molar conductance measurement in DMF solution confirmed that the complexes are nonelectrolytic. TGA analysis results showed that the thermal stability of the ligands and complexes was high. Antioxidant capacity and free radical scavenging activity of the mixed ligand Fe(III) complexes were investigated using CUPRAC and the DPPH radical scavenging method. Mixed ligand Fe(III) complexes showed higher antioxidant activity than ligands and reference compound. Popular conceptual density functional parameters like hardness, electrophilicity, dipole moment, and chemical potential for new ligands and their Fe(III) complexes were calculated and discussed. Chemical reactivity and stabilities of the studied chemical systems were analyzed with the help of well-known electronic structure principles like maximum hardness principle (MHP), hard and soft acid-base (HSAB) principle, minimum polarizability principle, and minimum electrophilicity principle. L1Fe, which has the highest chemical hardness value, is the most stable complex according to MHP

Grêmio estudantil : ação democrática

O presente trabalho se trata da apresentação do Projeto de Intervenção (PI) desenvolvido no âmbito do Curso de Especialização em Gestão Escolar, da Faculdade de Educação, da Universidade Federal do Rio Grande do Sul. Tem foco na criação de um Grêmio Estudantil, no primeiro semestre de 2015. Foi aplicado na EMEF Carlos Soares da Silveira, localizada em Canguçu. Tem a pesquisa-ação como forma de intervenção na realidade, pois onde surge um problema é necessário intervir de forma pedagógica para provocar uma mudança na realidade. Dentre os conceitos que sustentaram este projeto, destaco o da gestão democrática, pois através desta há uma abertura de diálogo, onde a criação do Grêmio Estudantil faz a ponte com a comunidade escolar. Foram desenvolvidas três das cinco etapas propostas para a criação do Grêmio: reuniões com a comunidade escolar para apresentação do trabalho que seria desenvolvido e formação das comissões; aprovação do Regimento Eleitoral e calendário eleitoral e exposição das propostas das chapas. Não foi possível a realização de todas as etapas do projeto devido a organização das datas previstas não ocorrerem na normalidade por paralisação das aulas pela mobilização em prol da educação e a constante chuva, privando os alunos de comparecerem às aulas. Apesar das dificuldades os alunos caminham em busca da concretização do Grêmio Estudantil, a eleição e a posse, promovendo ações dentro da escola

A Survey on Beekeeping Activities and Colony Losses in Turkey

Bu çalışmada, gezginci ve yerel kolonilerde besleme uygulamaları, kolonilerin seçilim yöntemleri, hastalıkların kontrol metotları ve 2008-2011 yılları arasındaki koloni kayıpları değerlendirilmiştir. Verilere göre arıcıların %92.6' ı kolonilerinde erken ilkbahar ve sonbahar beslemesi yapmaktadır. Yerli arıcıların bir kısmı (%37.7) ve göçer arıcılar (%62.4) kolonilerini beslemede şurup ve diğer besin maddelerinin ikisini birden tercih etmektedir. Arıcılar, saldırganlık davranışı olmayan ve yüksek bal verimi olan %47.6), ayrıca oğul verme davranışı yüksek olan (%14.2), hastalıklara dayanıklı (%5.2), kraliçe arının alt türüne ve fizyolojik özelliklerine göre kolonilerini seçmektedir. Kışlatmaya bağlı koloni kayıpları sırasıyla 2008-9 yıllarında %14.5, 2009-10 yıllarında %18.9 ve 2010-11 yıllarında %12.6 olarak gözlemlenmiştir. 2009-2010 yılları arasındaki koloni kayıpları arasında korelasyon önemli bulunmuştur (P<0.01). Çalışma düzenli saha tarama çalışmalarının koloni yönetiminin ve koloni kayıplarının takibinde önemli olduğunu işaret etmektedir.The study was planned to investigate colony feeding practices, the selection methods of colonies, the control methods of diseases, yearly losses from 2008 to 2011 in each operation and included both migratory and local colonies in Turkey. The beekeepers (92.6%) used to feed their colony in early spring and autumn with supplemental food. The most of local (37.7%) and migratory (62.4%) beekeepers preferred to feed their colonies with both syrup and supplemental food. The beekeepers generally prefer colonies that are not aggressive and with high honey production (47.6%) and also tendency to high swarming (14.2%), resistant to diseases (5.2%) and other factors such as subspecies and physiological characteristics of queens are causes of preference. The colony losses due to winter in 2008-9; 2009-10; 2010-11 were observed as 14.5%, 18.6%, 12.6%, respectively and also the significant correlation (P&lt;0.01) were found between 2009-2010. Our study reveals regular survey studies play a crucial role to improve both colony management and monitoring of colony losses