Mediastinal mass diagnosed as a benign schwannoma

Neurogenic tumours of the mediastinum are most commonly present in the posterior mediastinal compartment. Schwannomas, being the most frequently encountered type, can be either benign or malignant, although the former is more common. They typically appear as an asymptomatic mass on radiographic imaging. These tumours with spindle-shaped cells are often asymptomatic, and are routinely detected on standard pulmonary radiography. However, computed tomography and magnetic resonance imaging, especially for posterior mediastinal tumours, provide additional information and help to determine its possible extension to adjacent structures. Therefore, radiographic and histopathological examinations are vital diagnostic tools in the detection of these silent tumours. Complete surgical resection using video-assisted thoracic surgical technique is the mainstay of treatment, and offers an excellent prognosis

Hydrogen induced optically-active defects in silicon photonic nanocavities

This work was supported by Era-NET NanoSci LECSIN project coordinated by F. Priolo, by the Italian Ministry of University and Research, FIRB contract No. RBAP06L4S5 and by the EPSRC UKSp project. Partial financial support by the Norwegian Research Council is also acknowledged.We demonstrate intense room temperature photoluminescence (PL) from optically active hydrogen- related defects incorporated into crystalline silicon. Hydrogen was incorporated into the device layer of a silicon on insulator (SOI) wafer by two methods: hydrogen plasma treatment and ion implantation. The room temperature PL spectra show two broad PL bands centered at 1300 and 1500 nm wavelengths: the first one relates to implanted defects while the other band mainly relates to the plasma treatment. Structural characterization reveals the presence of nanometric platelets and bubbles and we attribute different features of the emission spectrum to the presence of these different kind of defects. The emission is further enhanced by introducing defects into photonic crystal (PhC) nanocavities. Transmission electron microscopy analyses revealed that the isotropicity of plasma treatment causes the formation of a higher defects density around the whole cavity compared to the ion implantation technique, while ion implantation creates a lower density of defects embedded in the Si layer, resulting in a higher PL enhancement. These results further increase the understanding of the nature of optically active hydrogen defects and their relation with the observed photoluminescence, which will ultimately lead to the development of intense and tunable crystalline silicon light sources at room temperature.Publisher PDFPeer reviewe

Hydrodynamics, Mass and Heat Transferin Reactive Distillation

The ethyl acetate synthesis via heterogeneous reactive distillation is studied experimentally using ethanol and acetic acid. Three types of cation exchanging resins were used as catalysts: Zerolit 225, Zerolit 226 and Ambylite 400. Experiments were carried out in two units of the same dimensions. Each unit consisted of three sections: rectifying, reactive and stripping sections of heights (60+25+20) cm respectively and 2.5cm column diameter. The first unit (column-A-) was a fractionation type and the second unit (column-B-) was packed column. The packing type was hollow glass cylinders with 10 mm height, and 4, 5 mm inner and outer diameter respectively. <br /> The experiments were carried out by using two operation modes. The semi-batch and continuous operation mode. In the first part of present investigation, the semi-batch mode was used to evaluate the catalyst type and to evaluate the performance of reactive distillation unit configuration (Fractionation and packed column). Results show that, the column-B- gave higher conversion rates than column-A-. This is attributed to the high surface area available for liquid vapour contact in packed type column, which leads to increasing mass transfer rates. On the other hand, Ambylite 400 catalyst showed higher activity for esterification reaction than other two types of catalysts. <br /> The second part of work continued with column -B- only. It is well known that, the esterification process is regarded one of exothermic reactions. Therefore, the monitoring of the temperature distribution along column axial for all three types of catalysts showed that the temperature distribution was essentially the same due to steady state operation in continuous operation mode. On the other hand, the effect of reflux ratio on temperature distribution was clearly noted, that is as the reflux ratio increased the temperature distribution along the column was reduced for each type of catalysts.<br /> On the other hand, the experimental results point that, as a reflux ratio increases the conversion rates of acetic acid is increased too because such increasing is related to high mass transfer rates between vapour and liquid along reactive distillation column. <br /

Outcomes of outpatient parenteral antimicrobial therapy (OPAT) for urinary tract infections – A single center retrospective cohort study

Background: Outpatient parenteral antimicrobial therapy (OPAT) is widely used to safely administer intravenous antibiotics in the outpatient setting. However, there are risks of treatment failure and clinical complications. We evaluate the outcomes of episodes of urinary tract infection (UTI) treated through OPAT at a large tertiary referral center in the UK. Methods: We retrospectively reviewed patient records of episodes of UTI treated for ≥ 2 days at the Sheffield Teaching Hospitals OPAT unit from 2017 to 2021. We defined OPAT and infection failure as unplanned 30-day hospital readmissions and symptomatic non-improvement, respectively. Univariate and multivariate logistic regression analyses were performed to analyze predictors of these outcomes. Results: 162 episodes of UTI in 115 patients were analyzed. OPAT failure was observed in 16.0 % (n = 26) of episodes, while infection remained unresolved in 8.0 % (n = 13) of episodes. Urolithiasis was an independent risk factor of both OPAT (odds ratio [OR], 4.3; 95 % confidence interval [CI], 1.2–16.1; p = 0.03) and infection failure (OR, 5.9; 95 % CI, 1.2–29.9; p = 0.03). Prior hospitalization also increased the risk of both OPAT (OR, 4.4; 95 % CI, 1.1–18.7; p = 0.04) and infection failure (OR, 8.0, 95 % CI, 1.3–78.4; p = 0.04). Conclusions: These results can assist clinicians at commencement of OPAT to identify patients at high risk of treatment failure. Wider network studies are required to further elicit the role of urolithiasis and its treatment to improve outcomes of UTI management in OPAT

Development and properties of polymeric nanocomposite coatings

Polymeric-based nanocomposite coatings were synthesized by reinforcing epoxy matrix with titanium nanotubes (TNTs) loaded with dodecylamine (DOC). The performance of the developed nanocomposite coatings was investigated in corrosive environments to evaluate their anti-corrosion properties. The SEM/TEM, TGA, and FTIR analysis confirm the loading of the DOC into the TNTs. The UV-Vis spectroscopic analysis confirms the self-release of the inhibitor (DOC) in response to the pH change. The electrochemical impedance spectroscopic (EIS) analysis indicates that the synthesized nanocomposite coatings demonstrate superior anticorrosion properties at pH 2 as compared to pH 5. The improved anticorrosion properties of nanocomposite coatings at pH 2 can be attributed to the more effective release of the DOC from the nanocontainers. The superior performance makes polymeric nanocomposite coatings suitable for many industrial applications.Qatar University, University of Auckland, Qatar FoundationScopu

Surrogate-based optimization of tidal turbine arrays: a case study for the Faro-Olhão inlet

This paper presents a study for estimating the size of a tidal turbine array for the Faro-Olhão Inlet (Potugal) using a surrogate optimization approach. The method compromises problem formulation, hydro-morphodynamic modelling, surrogate construction and validation, and constraint optimization. A total of 26 surrogates were built using linear RBFs as a function of two design variables: number of rows in the array and Tidal Energy Converters (TECs) per row. Surrogates describe array performance and environmental effects associated with hydrodynamic and morphological aspects of the multi inlet lagoon. After validation, surrogate models were used to formulate a constraint optimization model. Results evidence that the largest array size that satisfies performance and environmental constraints is made of 3 rows and 10 TECs per row.Eduardo González-Gorbeña has received funding for the OpTiCA project (http://msca-optica.eu/) from the Marie Skłodowska-Curie Actions of the European Union's H2020-MSCA-IF-EF-RI-2016 / GA#: 748747. The paper is a contribution to the SCORE pro-ject, funded by the Portuguese Foundation for Science and Technology (FCT–PTDC/AAG-TEC/1710/2014). André Pacheco was supported by the Portuguese Foun-dation for Science and Technology under the Portuguese Researchers’ Programme 2014 entitled “Exploring new concepts for extracting energy from tides” (IF/00286/2014/CP1234).info:eu-repo/semantics/publishedVersio

Self-healing performance of multifunctional polymeric smart coatings

Multifunctional nanocomposite coatings were synthesized by reinforcing a polymeric matrix with halloysite nanotubes (HNTs) loaded with corrosion inhibitor (NaNO3) and urea formaldehyde microcapsules (UFMCs) encapsulated with a self-healing agent (linseed oil (LO)). The developed polymeric nanocomposite coatings were applied on the polished mild steel substrate using the doctor's blade technique. The structural (FTIR, XPS) and thermogravimetric (TGA) analyses reveal the loading of HNTs with NaNO3and encapsulation of UFMCs with linseed oil. It was observed that self-release of the inhibitor from HNTs in response to pH change was a time dependent process. Nanocomposite coatings demonstrate decent self-healing effects in response to the external controlled mechanical damage. Electrochemical impedance spectroscopic analysis (EIS) indicates promising anticorrosive performance of novel nanocomposite coatings. Observed corrosion resistance of the developed smart coatings may be attributed to the efficient release of inhibitor and self-healing agent in response to the external stimuli. Polymeric nanocomposite coatings modified with multifunctional species may offer suitable corrosion protection of steel in the oil and gas industry. - 2019 by the authors.Acknowledgments: This publication was made possible by NPRP Grant 9-080-2-039 from the Qatar National Research Fund (a member of the Qatar Foundation). Statements made herein are solely the responsibility of the authors. This research work was also partially supported by QU internal grant-QUCG-CAM-2018/2019-3