Torus knots and Dunwoody manifolds

We obtain an explicit representation, as Dunwoody manifolds, of all cyclic branched coverings of torus knots of type $(p,mp\pm 1)$, with $p>1$ and $m>0$.Comment: 11 pages, 7 figures, to appear in the Siberian Mathematical Journa

VARIATION OF DISTRIBUTION COEFFICIENT OF CAFFEINE BETWEEN WATER AND ETHYL ACETATE/CHLOROFORM MIXTURE DEPENDING ON THE MEDIUM ACIDITY

Kafein, ülkemizde önemli bir tarımsal ürün olan ve büyük miktarlarda üretilen çayın enönemli bileşenidir. Kafein, çok yaygın ve farklı alanlardaki kullanımı nedeniyle büyük ticarideğer taşımaktadır. Bu nedenle, ekonomik üretim proseslerinin geliştirilmesi son dereceönemlidir.Bu çalışmanın amacı, kafeinin su ve etil asetat/kloroform karışımı arasındaki dağılmakatsayılarının pH\'a bağlı olarak değişiminin incelenmesidir. Çalışmada organik çözücükarışımı etil asetat/kloroformun beş farklı oranı kullanılmıştır. Bu oranlar %20, %40, %50,%60 ve %80 kloroform içerecek şekilde seçilmiştir. Ayrıca dağılma katsayısının pH\'yabağımlılığının incelenmesi için denemeler beş farklı pH\'da yapılmıştır. Bu pH değerleri 5.65,5.90, 6.25, 7.10 ve 7.90\'dır. Deneysel çalışmada hazırlanan % 1\'lik (hacimsel) kafeinçözeltisinden belirli miktar alınarak çözücü karışımı ile ekstrakt edilmiş ve iyodometriyöntemiyle kafein analizi yapılmıştır. Yapılan deneysel çalışmalar sonucunda, pH değerininyükselmesiyle dağılma katsayısının arttığı tespit edilmiştir.Caffeine is a main component of tea, which is an important agricultural product in ourcountry. It has a great economical value because of its different and extensive industrialapplications.The aim of this study is to investigate the variation of the distribution coefficients ofcaffeine between water and ethyl acetate/chloroform mixture depending on pH. Ethylacetate/chloroform mixture was used in five different ratios. These ratios were selected as tocontain 20%, 40%, 50%, 60% and 80% chloroform. Also five different pH were selected toinvestigate the distribution coefficient depending on pH. These pH values were 5.65, 5.90,6.25, 7.10 and 7.90.In experimental investigations, 1% aqueous solution of caffeine was used. Caffeinecontent was analysed by means of Iodometry method.It was seen that the distribution coefficient of caffeine between water and solvent mixturewas increased with increasing pH

VARIATION OF DISTRIBUTION COEFFICIENT OF CAFFEINE BETWEEN WATER AND ETHYL ACETATE/CHLOROFORM MIXTURE DEPENDING ON THE MEDIUM ACIDITY

Kafein, ülkemizde önemli bir tarımsal ürün olan ve büyük miktarlarda üretilen çayın enönemli bileşenidir. Kafein, çok yaygın ve farklı alanlardaki kullanımı nedeniyle büyük ticarideğer taşımaktadır. Bu nedenle, ekonomik üretim proseslerinin geliştirilmesi son dereceönemlidir.Bu çalışmanın amacı, kafeinin su ve etil asetat/kloroform karışımı arasındaki dağılmakatsayılarının pH\'a bağlı olarak değişiminin incelenmesidir. Çalışmada organik çözücükarışımı etil asetat/kloroformun beş farklı oranı kullanılmıştır. Bu oranlar %20, %40, %50,%60 ve %80 kloroform içerecek şekilde seçilmiştir. Ayrıca dağılma katsayısının pH\'yabağımlılığının incelenmesi için denemeler beş farklı pH\'da yapılmıştır. Bu pH değerleri 5.65,5.90, 6.25, 7.10 ve 7.90\'dır. Deneysel çalışmada hazırlanan % 1\'lik (hacimsel) kafeinçözeltisinden belirli miktar alınarak çözücü karışımı ile ekstrakt edilmiş ve iyodometriyöntemiyle kafein analizi yapılmıştır. Yapılan deneysel çalışmalar sonucunda, pH değerininyükselmesiyle dağılma katsayısının arttığı tespit edilmiştir.Caffeine is a main component of tea, which is an important agricultural product in ourcountry. It has a great economical value because of its different and extensive industrialapplications.The aim of this study is to investigate the variation of the distribution coefficients ofcaffeine between water and ethyl acetate/chloroform mixture depending on pH. Ethylacetate/chloroform mixture was used in five different ratios. These ratios were selected as tocontain 20%, 40%, 50%, 60% and 80% chloroform. Also five different pH were selected toinvestigate the distribution coefficient depending on pH. These pH values were 5.65, 5.90,6.25, 7.10 and 7.90.In experimental investigations, 1% aqueous solution of caffeine was used. Caffeinecontent was analysed by means of Iodometry method.It was seen that the distribution coefficient of caffeine between water and solvent mixturewas increased with increasing pH

Structural Analysis of the Essential Resuscitation Promoting Factor YeaZ Suggests a Mechanism of Nucleotide Regulation through Dimer Reorganization

Extent: 8p.Background: The yeaZ gene product forms part of the conserved network YjeE/YeaZ/YgjD essential for the survival of many Gram-negative eubacteria. Among other as yet unidentified roles, YeaZ functions as a resuscitation promoting factor required for survival and resuscitation of cells in a viable but non-culturable (VBNC) state. Methodology/Principal Findings: In order to investigate in detail the structure/function relationship of this family of proteins we have performed X-ray crystallographic studies of Vibrio parahaemolyticus YeaZ. The YeaZ structure showed that it has a classic actin-like nucleotide-binding fold. Comparisons of this crystal structure to that of available homologues from E. coli, T. maritima and S. typhimurium revealed two distinctly different modes of dimer formation. In one form, prevalent in the absence of nucleotide, the putative nucleotide-binding site is incomplete, lacking a binding pocket for a nucleotide base. In the second form, residues from the second subunit complete the nucleotide-binding site. This suggests that the two dimer architectures observed in the crystal structures correspond to a free and a nucleotide-bound form of YeaZ. A multiple sequence alignment of YeaZ proteins from different bacteria allowed us to identify a large conserved hydrophobic patch on the protein surface that becomes exposed upon nucleotide-driven dimer re-arrangement. We hypothesize that the transition between two dimer architectures represents the transition between the ‘on’ and ‘off’ states of YeaZ. The effect of this transition is to alternately expose and bury a docking site for the partner protein YgjD. Conclusions/Significance: This paper provides the first structural insight into the putative mechanism of nucleotide regulation of YeaZ through dimer reorganization. Our analysis suggests that nucleotide binding to YeaZ may act as a regulator or switch that changes YeaZ shape, allowing it to switch partners between YjeE and YgjD.Inci Aydin, Yumiko Saijo-Hamano, Keiichi Namba, Connor Thomas and Anna Roujeinikov

Extraction of Hydroxycarboxylic Acids with MIBK/Toluene Solutions of Amines

926-930Studies are reported on the extraction of glycolic, malic, and citric acids by alamine 336 and tri-n-octylamine dissolved in MIBK/toluene mixture (1:1 volume ratio). The effects of amine type and concentration on extraction of hydroxycarboxylic acids by amines are investigated. Formation of acid amine complexes is a dominating factor in the system under consideration .. The distribution coefficients and loading factors are calculated and reported

Extmcition of hydroxycarboxylic acids with MIBK/toluene solutions of amines

Studies are reported on the extraction of glycolic, malic, and citric acids by alamine 336 and tri-n-octylamine dissolved in MIBK/toluene mixture (1 : 1 volume ratio). The effects of amine type and concentration on extraction of hydroxycarboxylic acids by amines are investigated. Formation of acid amine complexes is a dominating factor in the system under consideration.. The distribution coefficients and loading factors are calculated and reported

Identifying, Monitoring, and Evaluating Sustainable Ecotourism Management Criteria and Indicators for Protected Areas in Türkiye: The Case of Camili Biosphere Reserve

Although many criteria and indicator sets have been developed for sustainable ecotourism management in many countries around the world, such a set of criteria and indicators has not been developed in Türkiye yet. The aim of this study was to develop sustainable ecotourism management criteria and indicators specific to Türkiye’s social, economic, and ecological differences and to investigate the possibilities of using this developed set in the sustainable management of the Camili Biosphere Reserve Area. The set that consisted of 12 criteria and 68 indicators prepared based on WTO and UNWTO criteria and indicator sets was used as a starting point. Within the scope of the Delphi method, as a result of three stages of repeated questionnaires, a set of criteria and indicators consisting of 11 criteria and 101 indicators was reached, based on the suggestions and consensus of four expert groups. In the next step, the adaptation and prioritization of the national sustainable ecotourism management criteria and indicator set for the Camili Biosphere Reserve Area were realized using the Analytical Hierarchy Process method, depending on the opinions of four local expert groups. As a result, it was concluded that the ecotourism activities carried out in the Camili Biosphere Reserve received a total score of 95.4 and that the ecotourism activities in the area were positively sustainable, with an average of 69.1%. It was determined that ecotourism activities in the Camili Biosphere Reserve are positively sustainable in terms of “level of awareness and perception of the field”, “socio-economic benefits to the local people”, “local participation”, “financial structure”, “environmental education and practices“, and “visitor satisfaction” criteria. However, in order to ensure the sustainability of ecotourism activities both at the country level and at the local level, studies should be carried out with a participatory approach by establishing a balance between the expectations of the local people and the income obtained from ecotourism, by providing a central authority, and by making improvements in the financing structure

Crystal structure of (2E)-1-(4-hydroxyphenyl)-3-(4-methoxyphenyl)prop-2-en-1-one

The compound, C16H14O3, (except H atoms) is almost planar [r.m.s. deviations for all non-H atoms = 0.001 Å] and the dihedral angle between the aromatic rings is 9.35 (7)°. In the crystal, molecules are linked by intermolecular O—H···O and C—H···O hydrogen bonds, forming a three-dimensional network structure. Furthermore, a weak π-π stacking interactions [centroid-to-centroid distance = 3.7055 (9) Å] contributes to the stabilization of the molecular packing. Crystal Data for C16H14O3 (M = 254.27 g/mol): Orthorhombic, space group Pbca (no. 61), a = 13.4563(16) Å, b = 11.4986(14) Å, c = 16.720(2) Å, V = 2587.1(5) Å3, Z = 8, T = 296(2) K, μ(MoKα) = 0.090 mm-1, Dcalc = 1.306 g/cm3, 61402 reflections measured (4.88° ≤ 2Θ ≤ 56.76°), 3240 unique (Rint = 0.0334, Rsigma = 0.0120) which were used in all calculations. The final R1 was 0.0438 (I≥2σ(I)) and wR2 was 0.1228 (all data)