Thin-film silicon solar cells are often deposited on textured ZnO substrates. The solar-cell performance is strongly correlated to the substrate morphology, as this morphology determines light scattering, defective-region formation, and crystalline growth of hydrogenated nanocrystalline silicon (nc-Si:H). Our objective is to gain deeper insight in these correlations using the slope distribution, rms roughness (σ(rms)) and correlation length (lc) of textured substrates. A wide range of surface morphologies was obtained by Ar plasma treatment and wet etching of textured and flat-as-deposited ZnO substrates. The σ(rms), lc and slope distribution were deduced from AFM scans. Especially, the slope distribution of substrates was represented in an efficient way that light scattering and film growth direction can be more directly estimated at the same time. We observed that besides a high σ(rms), a high slope angle is beneficial to obtain high haze and scattering of light at larger angles, resulting in higher short-circuit current density of nc-Si:H solar cells. However, a high slope angle can also promote the creation of defective regions in nc-Si:H films grown on the substrate. It is also found that the crystalline fraction of nc-Si:H solar cells has a stronger correlation with the slope distributions than with σ(rms) of substrates. In this study, we successfully correlate all these observations with the solar-cell performance by using the slope distribution of substrates.

PurposeThe use of barium enemas to confirm the anastomotic integrity prior to ileostomy closure is still controversial. The purpose of the study was to determine the utility of routine contrast enema prior to ileostomy closure and its impact on patient management in patients with a low pelvic anastomosis.MethodsOne hundred forty-five patients had a temporary loop ileostomy constructed to protect a low colorectal or coloanal anastomosis following low anterior resection for rectal cancer. All patients were evaluated by physical examination, proctoscopy, and barium enema prior to ileostomy closure.ResultsThe median time from ileostomy creation to closure was 8 months. Five (3.5%) of the 144 patients were found to have clinically relevant strictures at the colorectal anastomosis on routine barium enema. One patient (0.7%) showed anastomotic leak on their barium enema. Overall, 141 patients (97.9%) had an uncomplicated postoperative course. Postoperative complication occurred in three patients (2.1%). None of them showed abnormal barium enema finding, which suggested that routine contrast enema examination did not predict postoperative complication.ConclusionRoutine barium enema evaluation of low pelvic anastomoses before loop ileostomy closure did not provide any additional information for postoperative colorectal anastomotic complication.

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Nanostructured potassium-incorporated Ti-based oxides have attracted much attention because the incorporated potassium can influence their structural and physico-chemical properties. With the aim of tuning the structural and physical properties, we have demonstrated the wet corrosion process (WCP) as a simple method for nanostructure fabrication using various Ti-based materials, namely Ti–6Al–4V alloy (TAV), Ti–Ni (TN) alloy and pure Ti, which have 90%, 50% and 100% initial Ti content, respectively. We have systematically investigated the relationship between the Ti content in the initial metal and the precise condition of WCP to control the structural and physical properties of the resulting nanostructures. The WCP treatment involved various concentrations of KOH solutions. The precise conditions for producing K-incorporated nanostructured titanium oxide films (nTOFs) were strongly dependent on the Ti content of the initial metal. Ti and TAV yielded one-dimensional nanowires of K-incorporated nTOFs after treatment with 10 mol/L-KOH solution, whereas TN required a higher concentration (20 mol/L-KOH solution) to produce comparable nanostructures. The obtained nanostructures revealed a blue-shift in UV absorption spectra due to the quantum confinement effects. A significant enhancement of the photocatalytic activity was observed via the chromomeric change and the intermediate formation of methylene blue molecules under UV irradiation. This study demonstrates the WCP as a simple, versatile and scalable method for the production of nanostructured K-incorporated nTOFs to be used as high-performance photocatalysts for environmental and energy applications.