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Objective: To compare the assessment of intra-ovarian stromal vascularity through transabdominal ultrasonography with colour Doppler imaging, power Doppler imaging, colour superb microvascular imaging and monochrome superb microvascular imaging in polycystic ovary syndrome cases. Method: The retrospective cross-sectional study was conducted at the Obstetrics and Gynaecology outpatient department of the Usak Training and Research Hospital, Turkey, from April 11 to June 18, 2018, and comprised grayscale colour Doppler imaging, power Doppler imaging, colour superb microvascular imaging and monochrome superb microvascular imaging of women with polycystic ovary syndrome. The recorded video images were evaluated by three radiologists and rated through consensus decision. Mean values for age, body mass index, follicle stimulating hormone and l uteinizing hormone levels, luteinizing hormone-follicle stimulating hormone ratio, Ferriman Gallwey score, and mean ovarian volume of the subjects were evaluated. Data was analysed using Number Cruncher Statistical System. Results: Of the 54 women evaluated, data of 42(77.8%) was included. There were a total of 83 ovaries, as the left ovary of 1(1.2%) patient was not visible. The mean age and body mass index were 24.02±5.8 years and 25.08±4.5kg/m2. Mean follicle stimulating hormone and luteinizing hormone levels were 5.51±1.91 and 7.91±6.13m IU/mL. Luteinizing hormone/follicle stimulating hormone ratio and Ferriman Gallwey score were 1.4±0.8 and 8.67 ±6.94, respectively. The mean ovarian volume was 12.2±3.43 cm3. The detection of vascularity was colour Doppler imaging 0.72±0.97, power Doppler imaging 0.96±1.08, colour superb microvascular imaging 2.47±1.25, and monochrome superb microvascular imaging 2.75±1.31. The techniques were significant for superb microvascular imaging Doppler than conventional Doppler (p

Conjugated polymer photocatalysts have been receiving extensive attention in the field of photocatalytic hydrogen evolution, owing to their tunable molecular structures and electronic properties. Herein, we report a hyperbranched conjugated polymer, containing thienothiophene and anthracene units (TT-Ant), synthesized via Pd(0) catalyzed Suzuki coupling. Its structural, photophysical and electrochemical features were investigated by using UV-vis and fluorescence spectroscopy, cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS). Photocatalytic hydrogen evolution tests, combining the material with two different additives, resulted in high hydrogen production rates from water. A steady state production rate of around 286 μmol g−1 h−1 for its hybridization with TiO2 was recorded, which is more than 3 times that for pristine TiO2 under the same conditions. Moreover, the combination of the polymeric material with platinum (1% wt) resulted in a maximum rate value of 700 μmol g−1 h−1. The surface properties of the latter combination before and after the reaction were studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which demonstrated successful Pt deposition on the surface of the polymer. This work may provide a new strategy to construct stable photocatalysts with thienothiophene and anthracene cores as active sites for efficient catalytic reactions in energy conversion applications. [ABSTRACT FROM AUTHOR]

A novel method based on light‐induced fabrication of a poly (3,4‐ethylenedioxythiophene)‐polycaprolactone (PEDOT‐PCL) scaffold using phenacyl bromide (PAB) as a single‐component photoinitiator is presented. HBr released from the step‐growth polymerization of EDOT is utilized as an in situ catalyst for the chain‐growth polymerization of ε‐caprolactone. Detailed investigations disclose the formation of a self‐assembled nanoporous electroconductive scaffold (1.2 mS cm−1). Fluorescence emission spectra of the fabricated scaffold exhibit a mixed solvatochromic behavior, indicating specific interactions between the self‐assembled scaffold and solvents with varying polarities, as evidenced by transmission electron microscopy (TEM). Moreover, the same light‐induced technique can also be applied for bulk photopolymerization showcasing the versatility and wide‐ranging scope of the originated method. In brief, this study introduces a novel approach for light‐induced polymerization reactions that is merging step‐growth and chain‐growth mechanisms. This innovative approach is promising to facilitate in situ polymerization of monomers possessing diverse functionalities. [ABSTRACT FROM AUTHOR]

Three novel donor–acceptor-based conjugated polymers with a naphthalenedimide-thienothiophene backbone, possessing electron acceptor nitrile (CN) and electron donor methoxy (OMe) groups and an acetylene spacer were designed and synthesized. They were successfully obtained via Stille and Sonogashira couplings and were characterized using UV-Vis spectrometry, cyclic voltammetry and DFT studies. They were used to fabricate organic field-effect transistors (OFETs) and organic phototransistors (OPTs) devices. All the polymers exhibited n-type behavior in bottom-gate and top-contact organic thin-film transistors. Regarding the OPT devices, while the polymer with the CN moiety showed the highest photosensitivity P value (209), the copolymer containing the acetylene spacer and electron donor methoxy group exhibited the largest photoresponsivity R-value (2.2 × 106 A W−1). Our findings demonstrated that the introduction of various functional groups and a triple bond spacer is an effective approach for manipulating the optical and electronic properties, as well as enhancing the overall performance of the devices. [ABSTRACT FROM AUTHOR]

In this work, copolymers of dithienothiophenes (DTT) and DTT-4,4-dioxide (DTT-S,S-[O.sub.2]) with mesitylboron were prepared for optoelectronic applications. Optical and electrochemical investigations were performed giving rise to the band gaps of 2.46-3.21 and 2.18-2.88 eV, respectively. Copolymers possessing DTT-S,S-[O.sub.2] units demonstrated the lower band gaps. Density functional theory investigations of the model compounds revealed the presence of an intramolecular charge transfer transition between the donor DTT units and the boron acceptor atoms., INTRODUCTION In recent times, syntheses of donor-acceptor (D-A) type conjugated organic polymers for optoelectronic applications have been demonstrated [1-6]. Among them, oligomers and polymers possessing a three-coordinate boron atom as [...]