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TiO2 is gaining interest as material for integrated photonics, due to its high refractive index, large transparency window and high non-linear refractive index. Its low phonon energy makes it attractive for the realization of active devices in the visible frequency range. In this work, we optimize different process steps of the fabrication of low loss TiO2 channel waveguides. The TiO2 layers are deposited by DC sputter deposition, using a mixed Ar/O2 plasma. Removing the hysteresis in the deposition process, results in reduced propagation losses of the TiO2 films (estimated less than 1.5 dB/cm at 632 nm wavelength). An E-beam lithography process is utilized to reduce the sidewall roughness of the waveguides. Different reactive gasses are compared to optimize the reactive ion etching recipe. BCl3 in combination with HBr shows to be most beneficial for etching TiO2 with high selectivity towards negative E-beam resist. A selectivity of 2.7 for TiO2 over the E-beam resist is obtained. The performance of a TiO2 a channel waveguide fabricated with the process before and after optimization is compared. The waveguide fabricated using the non-optimized process exhibited losses of 7.82±0.52 dB/cm at a wavelength of 632.8 nm, after applying an SiO2 cladding. After process optimization, 5.08±0.65 dB/cm were obtained, without an SiO2 cladding.

Background Contaminant DNA is a well-known confounding factor in molecular biology and in genomic repositories. Strikingly, analysis workflows for whole-genome sequencing (WGS) data commonly do not account for errors potentially introduced by contamination, which could lead to the wrong assessment of allele frequency both in basic and clinical research. Results We used a taxonomic filter to remove contaminant reads from more than 4000 bacterial samples from 20 different studies and performed a comprehensive evaluation of the extent and impact of contaminant DNA in WGS. We found that contamination is pervasive and can introduce large biases in variant analysis. We showed that these biases can result in hundreds of false positive and negative SNPs, even for samples with slight contamination. Studies investigating complex biological traits from sequencing data can be completely biased if contamination is neglected during the bioinformatic analysis, and we demonstrate that removing contaminant reads with a taxonomic classifier permits more accurate variant calling. We used both real and simulated data to evaluate and implement reliable, contamination-aware analysis pipelines. Conclusion As sequencing technologies consolidate as precision tools that are increasingly adopted in the research and clinical context, our results urge for the implementation of contamination-aware analysis pipelines. Taxonomic classifiers are a powerful tool to implement such pipelines.

The present study refers to the effect of metal pollution on diatoms by describing a new form of teratology. The samples were collected in the Abrud River, located in a mining area from Romania, where an unreported type of deformity is observed in the diatoms Achnanthidium sp. pl. This kind of teratology has been found in the 20.5% of individuals of the population and affects the cingulum, in particular to the valvocopula, by becoming markedly undulate., Annali di Botanica, Vol 9 (2019)

Loss-of-function mutations in the cytosine-5 RNA methylase NSUN2 cause neurodevelopmental disorders in humans, yet the underlying cellular processes leading to the symptoms that include microcephaly remain unclear. Here, we show that NSUN2 is expressed in early neuroepithelial progenitors of the developing human brain, and its expression is gradually reduced during differentiation of human neuroepithelial stem (NES) cells in vitro. In the developing $\textit{Nsun2}$$^{-/-}$ mouse cerebral cortex, intermediate progenitors accumulate and upper-layer neurons decrease. Loss of NSUN2-mediated methylation of tRNA increases their endonucleolytic cleavage by angiogenin, and 5' tRNA fragments accumulate in $\textit{Nsun2}$$^{-/-}$ brains. Neural differentiation of NES cells is impaired by both $\textit{NSUN2}$ depletion and the presence of angiogenin. Since repression of NSUN2 also inhibited neural cell migration toward the chemoattractant fibroblast growth factor 2, we conclude that the impaired differentiation capacity in the absence of NSUN2 may be driven by the inability to efficiently respond to growth factors.

Esta monografía presenta una reformulación de la metodología de discontinuidades fuertes de continuo para la simulación numérica del fallo material de estructuras. Los objetivos buscados han sido mejorar la robustez de este tipo de análisis numérico y proporcionar una serie de herramientas que garanticen la confiabilidad de los resultados obtenidos. La metodología de discontinuidades fuertes de continuo [50]-[51] es una aproximación numérica al fenómeno de la localización de deformaciones por ablandamiento. Al contrario de las aproximaciones discretas, utiliza un formato continuo tensión-deformación para describir todo el proceso de agotamiento del material. Gracias a una regularización (reinterpretación) de la cinemática del problema y del módulo de ablandamiento se garantiza que la disipación del modelo venga dada por la densidad superficial de energía de fractura [52]. Adicionalmente, la utilización de un algoritmo tipo térmico de captura y gestión de las superficies de localización de deformaciones permite abordar el análisis de problemas con multifisuración [57]. La mejora en la robustez del análisis numérico se ha conseguido adoptando la formulación simétrica cinemáticamente consistente y formulando un nuevo esquema de integración, denominado IMPL-EX, que garantiza la definición positiva de los operadores algorítmicos que intervienen en el problema. La confiabilidad en el resultado numérico se asegura mediante un algoritmo de control del error cometido y mediante un nuevo esquema de limitación de la longitud de arco. Estos dos algoritmos han sido desarrollados específicamente para el esquema de integración IMPL-EX. La formulación así definida ha sido aplicada en el estudio de dos fenómenos propios de la mecánica de la fractura: el estudio de la influencia del tamaño de una estructura en su resistencia nominal (efecto tamaño) y el estudio/medición de la longitud de procesamiento de fractura. Por último se presentan una serie de ensayos numéricos del fallo material en estructuras tridimensionales. Estos ensayos se dividen en tres grupos: ensayos donde el modo de fallo predominante es en modo I, ensayos donde el modo de fallo predominante es de deslizamiento (análisis de taludes) y ensayos donde el modo de fallo moviliza mecanismos resistentes tridimensionales (análisis del efecto arco en presas con simple y doble curvatura).

BACKGROUND: Primary hydatid disease in the colon is an extremely rare finding. We performed a systematic review of cases of hydatidosis of the colon published to date. AIM: To systematic review the published papers about hydatidosis of the colon. METHODS: Following PRISMA guidelines, we performed an unlimited search for articles on CH in the MEDLINE (PubMed), EMBASE, Cochrane, Latindex and Scielo databases, published in English, Spanish, French, German or Italian between January 1, 1960 and December 15, 2018. The search items were: (Colon) AND [(hydatidosis) OR (hydatid disease) OR (echinococcosis)]. RESULTS: Nine case reports were found [five men, four women, median age 64.55 years (range: 21-81)]. The most frequent clinical manifestation was abdominal pain (8/9) (88.9%). In almost all cases several image studies were carried out, but abdominal computed tomography was the most used (66.7%). Five resections of the colon (62.5%) and three sutures of the fistula between cyst and colon (37.5%) were performed. Four patients did not present post-operative complications, but one died. Postoperative period was recorded for a mean period of 35 months. No recurrences were recorded. CONCLUSION: The most frequent symptom was abdominal pain (evidence level 4). Computed tomography was the most frequently used diagnostic imaging technique (evidence level 4). Colectomy was the most appropriate treatment (evidence level 5). All the diagnostic and therapeutic options for hydatid cysts located in colon have a low level of evidence.

Reliable speed of sound, c, values in CO2- rich mixtures and pure CO2 are required for carbon capture and storage (CCS) technology but are difficult to determine, particularly at relatively high frequencies. We tested the suitability of methanol as doping agent to obtain accurate c values in CCS systems at 5 MHz. We measured c in seven CO2-rich, CO2 + methanol mixtures between 263.15 and 323.15 K and up to 196.30 MPa, and we extrapolated the values to obtain c in pure CO2. Additionally, we measured c from 263.15 to 373.19 K and up to 190.10 MPa in two CO2-rich, CO2 + SO2 mixtures with the same SO2 composition, which is of interest for CCS, with one mixture doped with methanol. We compared our results for pure CO2 with the literature and the Span and Wagner equation of state (EoS). We validated the PC-SAFT EoS and the modeling with the REFPROP 9 software for the mixtures by comparing the predicted values with our experimental data under the studied conditions. We conclude that methanol is a suitable doping agent to measure c in pure CO2 and CO2-rich mixtures. For the CO2 + SO2 mixtures, the effect of methanol on the experimental values is small and negligible for modeling.