•We determine morphological, optical and electrical characteristics of DSSCs.•The TiO2 nanotubes’ length is important parameter that influences cell performance.•The reduction of incident light ...reaching the working electrode is significant.•Post treatment of titania nanotubes can have a various effect on cell performance.
Self-ordered, vertically aligned, titanium oxide (TiO2) nanotubes were grown on an electropolished titanium foil by anodic oxidation in a viscous organic electrolyte. We chose two different anodization times to obtain nanotubes of approximately 9 and 17μm in length. Some of the TiO2 nanotubes were post-treated with TiCl4 or hydrothermally with TiO2 P25. Their structure and morphology were investigated with field-emission scanning electron microscopy (FSEM) and transmission electron microscopy (TEM). To improve the sensitizing of the high-aspect-ratio nanotubes with dye we used a new approach in which the TiO2 arrays were immersed into the dye solution at elevated temperature in an autoclave. The current–voltage characteristics of the assembled DSSCs gave an average energy-conversion efficiency of 5.7% for the untreated nanotubes.
Background To overcome obstacles within the Slovenian organised cervical cancer screening programme, a randomised pilot study of human papillomavirus (HPV) self-sampling among non-attenders was ...performed, aiming to assess three different screening approaches. Participants and methods Non-attenders aged 30-64 years from two Slovenian regions were randomised to two HPV self-sampling groups-the opt-in (I1, n = 14.400) and the opt-out (I2, n = 9.556), with a control group (P, n = 2.600). Self-collected samples were analysed using the Hybrid Capture 2 assay. HPV-positive women were invited to a colposcopy. The overall and type-specific intention-to-screen response rates and histological outcomes with a positive predictive value (PPV) according to the women's age, the screening approach, the level of protection resulting from previous screening history, and the region of residence were assessed. Results Of the 26.556 women enrolled, 8.972 (33.8%) responded with self-sample for HPV testing and/or traditional cytology within one year of enrolment. Response rates were 37.7%, 34.0% and 18.4% (p < 0.050) for opt-out, opt-in and control groups. Cervical intraepithelial neoplasia (CIN)2+ was diagnosed in 3.9/1.000, 3.4/1.000, and 3.1/1.000 women (p > 0.050), respectively. PPV of the HPV self-sampling was 12.0% and 9.6% for CIN2+ and CIN3+. The highest PPV was obtained in non-attenders in screening programme for more than 10-years and concordant results of HPV testing with 40.8% for CIN2+ and 38.8% for CIN3+. Conclusions The results of our study show that a high response to HPV self-sampling can be achieved also in an opt-in approach, if women are encouraged to choose between self-sampling at home and screening with gynaecologist. In addition, clinically important risk difference for a high-grade cervical lesion exists in the case of a positive result of HPV testing on self-collected samples, depending on the length of the interval since last screening. Stratified management of these women should be strongly considered. Women who were not screened with cytology for at least 10 years should be referred to immediate colposcopy for histology verification instead to delayed re-testing.
p16/Ki-67 dual immunocytochemical staining (DS) has been proven as a sensitive and specific test for triage of HPV positive women with good reproducibility and accuracy. However, implementation of ...the test into an organized screening program (OSP) is not easy. The aims of this study were to compare the performance and agreement of DS results among three Slovenian cytopathological laboratories involved in the national OSP, and to define cases where staining results can be difficult to interpret.
Cervical smears were obtained for DS from 129 women referred to colposcopy. Smears were evaluated blindly in three laboratories by a cytotechnologist and a cytopathologist after initial training. Results were positive, suspicious, negative or inadequate. Five characteristics of DS staining were recorded. After primary evaluation, an extensive expert-led additional training was undertaken, including a discussion of difficult cases and a practical exam. Smears were re-evaluated and results compared to primary evaluation.
After the additional training, the overall percentage of agreement among the three laboratories increased from 77.5 to 89.9% and kappa increased from 0.70 to 0.86. Sensitivity for CIN2+ increased in two laboratories, to 90.5 and 85.7%, without the loss of specificity (75.8%). In one laboratory, the sensitivity slightly decreased from 90.5 to 88.9%, but the specificity increased from 63.6 to 68.2%. Difficult cases had significantly less DS cells, weak intensity of p16 staining, suboptimal cell morphology and background staining compared to positive cases.
Additional expert-led training and discussion of difficult cases are necessary for accurate interpretation of DS in laboratories involved in OSP. The most difficult cases were those with single stained cells and weak p16 staining. Training protocol for safe implementation of p16/Ki-67 DS in OSP is proposed.
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