3D acousto-optic modulated-speckle imaging in biological tissues

A parallel, 64K-channel implementation of the acousto-optic method of imaging optical contrasts buried in organs is presented. This implementation also associates this method with echography in a single apparatus. This allows us to prove that sensitivity to purely optical contrast is achieved. Moreover, this enables any potential user to distinguish easily optical contrast, acoustic contrast, and mixtures of both. We plan to improve this prototype with a view to future use by physicians in a hospital environment.     

Synthesis,Crystal Structure and Hirshfeld Surface Analysis of Ethyl 4-(4-(2-Bromoethyl)-1H-1,2,3-triazol-1-yl)benzoate

Crystallography Reports - The title compound, C13H14BrN3O2, was synthesized by click chemistry (CuAAC) using 4-bromobut-1-yne and ethyl 4-azidobenzoate. Its molecular structure was determined by 1H...     

A road map to assess critical materials content in boron industrial wastes using sustainable micro-X-ray fluorescence and total reflection X-ray fluorescence instrumentation

Turkey is the leading country in the world in terms of boron production and sale. Increasing boron production goes along with an increasing generation of boron wastes. The pollution of the soil and the air around the waste piles, as well as the occupation of several square kilometers of ground, are major environmental problems. It is, therefore, very important to make use of the wastes to both protect the environment and create revenue. This work presenteda road map for fast screening of boron waste for critical elements followed by determination of the elements using small footprint low power instrumentation. The sample preparation was kept to a minimum. A procedure that allowed an assessment of critical materials in industrial production waste with minimal consumption of hazardous acids, energy, and time was presented. The samples were first screened for valuable and hazardous elements by micro-X-ray fluorescence (XRF). Samples with considerable contents of Cs, Rb, and Aswere then prepared as slurries for the total reflection XRF (TXRF) measurement. To evaluate the TXRF procedure, a standard reference material was analyzed. As a result, Rb and Cs in concentrations up to 420 ± 70 and 1500 ± 200 mg/kg were detected in some of the waste forms. The time savings were in order of a factor of 3 when comparing the prescreening combined micro-XRF and TXRF approach to an all TXRFanalysis approach.     

Synthesis,characterization, and antioxidant and anticholinesterase activities of pyrazolo derivatives

Twenty-four pyrazolo derivatives (1–4)(a-f) were synthesized and characterized by FTIR, ¹H, and ¹³C NMR (Nuclear Magnetic Resonance), and elemental analysis. The synthesized compounds were also investigated for their antioxidant and anticholinesterase activities. The compounds (3–4)(a-f) carrying morpholine ring were more active than the piperidinyl containing compounds (1–2)(a-f) in both activities. The compound 4f showed higher activity in both assays as compared with the others. Additionally, the anticholinesterase activity test provided higher values than the galantamine in the BChE assay. Therefore, compound 4f can be used as anticholinesterase agent and/or anticholinesterase assay standard.     

Heterostructured MgO/ZnO photocatalysts: Synthesis,Characterization and UV Light-Induced Photocatalytic Activity Using Model Pollutant 2,6-dichlorophenol

ZnO and MgO/ZnO (mass ratio 2: 5, 5: 5 and 8: 5) heterostructure photocatalysts (Mg₂Zn₅, Mg₅Zn₅ and Mg₈Zn₅, respectively) were successfully synthesized via co-precipitation method. MgO/ZnO composites were characterized by scanning electron microscopy (SEM), X-Ray diffraction and low temperature nitrogen adsorption–desorption isotherm. According to SEM images all composites consisted of spherical granules with particle sizes of 30–50 nm. The band gap value of ZnO was found to be lower than that of MgO/ZnO composites as observed during the optical studies. Pure ZnO showed lower photocatalytic activity (38%) in the degradation of 2,6-dichlorophenol (2,6-DCP) than MgO/ZnO composites. Mg₅Zn₅ composite with a higher concentration of defects in crystallites was more active in the photocatalytic degradation (79.5%) than Mg₈Zn₅ (61.2%) and Mg₂Zn₅ (63.5%). High-resolution mass spectrometry-and UV-Vis spectroscopic analysis of the by-products, derived from model pollutant 2,6-DCP, proved the successful photocatalytic performance of Mg₅Zn₅ under the UV light. The synthesized composites are future candidates against other potential environmental pollutants.     

Characterization of fossil Sequoioxylon wood using analytical instrumental techniques

In this study, fossil (Sequoioxylon) wood from the Oligocene–Miocene transition in İstanbul, Turkey was examined using non-destructive test methods to evaluate changes in anatomical and chemical structure. Molecular changes in the cell wall structure of the wood were determined using Fourier transform infrared (FTIR) and FT-Raman spectroscopy, along with the comparison to recent wood [Sequoiadendron giganteum (Lindl.)]. We found that the cell wall carbohydrates of the fossil wood were significantly more degraded compared with lignin; FT-Raman spectroscopy revealed the degradation in more detail compared with FTIR spectroscopy. FT-Raman spectra also demonstrated that hemicellulose and holocellulose were decreased in the fossil wood. Laser-induced breakdown spectroscopy (LIBS) analysis confirmed that the mass loss was due to the decreased H and O content of the fossil wood sample and was caused by decomposition. Light microscopy also showed that fossil and recent woods have similar anatomic structures, and that the micro-morphological structure of the fossil wood was well-preserved.     

Copper(II) complexes of acylhydrazones: synthesis,characterization and DNA interaction

Two new acylhydrazone copper(II) complexes of 4‐hydroxy‐N′‐[(1E)‐1‐(4‐methylphenyl)ethylidene]benzohydrazide (HL¹) and 4 ethyl [4‐({(2E)‐2‐[1‐(4‐methylphenyl)ethylidene]hydrazinyl}carbonyl)phenoxy]acetate (HL²) have been synthesized and characterized. The structures of both acylhydrazone and copper(II) complexes were identified by elemental analysis, infrared spectra, UV–visible electronic absorption spectra, magnetic susceptibility measurements, TGA and powder X‐ray diffraction. DNA binding and DNA cleavage activities of the synthesized copper complexes were examined by using UV‐visible titration and agarose gel electrophoresis, respectively. The effect of complex concentration on the DNA cleavage reactions in the absence and presence of H₂O₂ was also investigated. The results indicate that all the complexes bind slightly to calf thymus DNA and cleavage pBR322 DNA. The mechanistic studies demonstrate that a hydrogen peroxide‐derived species and singlet oxygen (¹O₂) are the active oxidative species for DNA cleavage. Copyright © 2013 John Wiley & Sons, Ltd.     

Pathwise uniqueness for perturbed versions of Brownian motion and reflected Brownian motion

Any solution of the functional equation

Differential Operators and the Steenrod Algebra

The Novikov-Landweber algebra and the Steenrod algebra are setup in terms of the primitive differential operators acting in the usual way on the integralpolynomial ring Z[x₁,... ,x_n,...]. A commutative wedge productV for differential operators is introduced and it is shown thatthe iterated wedge product is divisible by r! as an integral operator. The divided differentialoperator algebra D is generated over the integers by thedividedoperators under the wedge product. D is additively isomorphic to the abelian group ofsymmetric functions in the variables x_i. Furthermore D is closedunder composition of operators and admits a natural coproductwhich makes it a Hopf algebra in two ways, with respect to thecomposition and wedge products. Under composition D is isomorphicto the Landweber-Novikov algebra. A Hopf sub-algebra is generatedunder composition by the integral Steenrod squares and reduces mod 2 to the Steenrod algebra. An explicitproduct formula for two wedge expressions is developed and usedto derive Milnor's product formula for his basis elements inthe Steenrod algebra. The hit problem in the Steenrod algebrais reformulated in terms of partial differential operators.1991 Mathematics Subject Classification: 55S10.