The histology of ovarian cancer: worldwide distribution and implications for international survival comparisons (CONCORD-2)

Objective Ovarian cancers comprise several histologically distinct tumour groups with widely different prognosis. We aimed to describe the worldwide distribution of ovarian cancer histology and to understand what role this may play in international variation in survival. Methods The CONCORD programme is the largest population-based study of global trends in cancer survival. Data on 681,759 women diagnosed during 1995â\u80\u932009 with cancer of the ovary, fallopian tube, peritoneum and retroperitonum in 51 countries were included. We categorised ovarian tumours into six histological groups, and explored the worldwide distribution of histology. Results During 2005â\u80\u932009, type II epithelial tumours were the most common. The proportion was much higher in Oceania (73.1%), North America (73.0%) and Europe (72.6%) than in Central and South America (65.7%) and Asia (56.1%). By contrast, type I epithelial tumours were more common in Asia (32.5%), compared with only 19.4% in North America. From 1995 to 2009, the proportion of type II epithelial tumours increased from 68.6% to 71.1%, while the proportion of type I epithelial tumours fell from 23.8% to 21.2%. The proportions of germ cell tumours, sex cord-stromal tumours, other specific non-epithelial tumours and tumours of non-specific morphology all remained stable over time. Conclusions The distribution of ovarian cancer histology varies widely worldwide. Type I epithelial, germ cell and sex cord-stromal tumours are generally associated with higher survival than type II tumours, so the proportion of these tumours may influence survival estimates for all ovarian cancers combined. The distribution of histological groups should be considered when comparing survival between countries and regions

Chloride atomic-layer chemical vapor deposition of TiO2 with a chloride pretreatment of substrates

A procedure for changing the course of the atomic-layer chemical vapor deposition (ALCVD) growth of TiO2 from TiCl4 and H2O on amorphous SiO2 substrates/underlayers at low temperatures is proposed. The changes are characterized by the real-time incremental dielectric reflection measurements and post-growth spectrophotometry and reflection high-energy electron diffraction measurements. In the procedure, an ultrathin layer of the material is deposited and, subsequently, in situ inhomogeneously etched in the TiCl4 flow, both steps being performed at a temperature above 350°C. As a result, an ultrathin microrough mixed amorphous/anatase-phase surface layer is created. By using this layer as a seed layer, the crystalline-growth temperature of the material is reduced. So anatase (mixed with amorphous phase) TiO2 thin films on SiO2 substrates at 125°C are, for the first time, grown. The films are shown to be depth-inhomogeneous. The upper part of the films, when they are thicker, is well texture

High nitrification rate at low pH in a fluidized bed reactor with either chalk or sintered glass as the biofilm carrier

A nitrification process using a fluidized bed reactor with chalk (solid calcium carbonate) as the biomass carrier and the only buffer agent was studied. The pH established in the reactor varied between 4.5 to 5.5, with lower pH obtained at higher nitrification rates. In spite of the low pH, high rate nitrification was observed with the nitrification kinetic parameters in the chalk reactor similar to those of biological reactors operating at pH > 7. Results from microsensor measurements refuted the possibility that favorable pH micro‐conditions prevailed on the chalk particles and contributed to high reactor performance. In addition, identification of the major bacterial species in the low pH chalk reactors revealed well‐known nitrifying bacteria. Based on these results, the performance of a fluidized bed reactor with porous sintered glass particles as the carrier for the biofilm (instead of chalk particles) was tested at similar low pH for comparison purposes. In contrast to the common knowledge of the nitrifers high sensitivity to low pH, the results from the non‐chalk biofilm reactor showed that well‐known nitrifying bacteria have the ability to nitrify at a high rate at low pH in a biofilm reactor using an inert (sintered glass) carrier

Effect of high electron donor supply on dissimilatory nitrate reduction pathways in a bioreactor for nitrate removal

The possible shift of a bioreactor for NO3 removal from predominantly denitrification (DEN) to dissimilatory nitrate reduction to ammonium (DNRA) by elevated electron donor supply was investigated. By increasing the C/NO3 ratio in one of two initially identical reactors, the production of high sulfide concentrations was induced. The response of the dissimilatory NO3 reduction processes to the increased availability of organic carbon and sulfide was monitored in a batch incubation system. The expected shift from a DEN-towards a DNRA-dominated bioreactor was not observed, also not under conditions where DNRA would be thermodynamically favorable. Remarkably, the microbial community exposed to a high C/NO3 ratio and sulfide concentration did not use the most energy-gaining process. (C) 2014 Elsevier Ltd. All rights reserved

Characterization of denitrifying granular sludge with and without the addition of external carbon source

In this study granular sludge taken from a denitrifying upflow sludge reactor was characterized. Denitrification rates were determined in batch tests with and without external carbon source addition and pH microprofiles of the granules were studied. The microbial community structure was also determined. The results showed that denitrification without carbon source addition occurs; however, the process rate was lower than with external carbon source. This suggests that bacteria use dead biomass and extracellular material in the granular sludge as a carbon source when readily available substrate has been exhausted and nitrate is still present. Microprofiles showed a slight pH decrease for denitrification without external carbon source addition, and an increase in pH when using nitrite as the electron acceptor. Microprofiles using acetate as the carbon source for denitrification showed a significant increase in pH. Clone sequences obtained were close to the species Vitellibacter sp., Denitromonas indolicum str. and Denitromonas aromaticaus sp

Study of thin oxide films by electron, ion and synchrotron radiation beams

Titanium oxide and zirconium oxide thin films deposited on silicon substrates were characterised using electron probe microanalysis (EPMA), Rutherford backscattering spectroscopy (RBS), time-of-flight elastic recoil detection analysis (TOF-ERDA) and scanning photoelectron microscopy (SPEM). The composition and mass thickness of the films were determined and the results of different methods compared. It was revealed that the synchrotron radiation used for SPEM studies caused considerable modification of zirconia films grown at low temperatures

Effective control of filament efficiency by means of spacer HfAlOx layers and growth temperature in HfO2 based ReRAM devices

Producción CientíficaResistive switching random access memories are being thoroughly studied as prospective non-volatile memories. In this paper, we report electrical characterization of HfO2:Al2O3based metal-insulator–metal structures devised using atomic layer deposition. Dependences of electrical behavior on HfO2:Al2O3 cycle ratio is studied. An explanation for the differences between the Resistive Switching properties of the samples is proposed, based on the distribution of HfAlOx layers of the sample. Dependence of the RS properties of the samples on their growth temperature is discussed.Ministerio de Ciencia, Innovación y Universidades con el apoyo de fondos Feder (grant TEC2017-84321-C4-2-R)Fondo Europeo de Desarrollo Regional "Pedidos emergentes en cuanto a cuántica y nanomateriales" (TK134)Estonian Research Agency (PRG753