Determination of the hydrodynamic performance of marine propellers using fibre Bragg gratings

Downloading of the abstract is permitted for personal use only. A critical aspect in the design of marine propellers is their hydrodynamic performance which, when evaluated experimentally, requires a number of parameters to be monitored at the same time, i.e.The thrust and torque a propeller generates as well as the propeller shaft and vessel speed. In this investigation, three of those parameters are measured using Fibre Bragg Grating-based sensors, thus allowing for computationally derived performance values to be verified. For that purpose, open water tests were carried out where an instrumented propeller shaft was installed into a research vessel and measurements taken, evaluated and the results compared favorably with advanced computer-based simulations

Matching conducted EMI to international standards

In this paper, the authors present a methodology that allows them to accommodate the conducted electromagnetic interference (EMI) generated by power factor correctors to international standards in the design step. EMI filter design considerations and EMI predictive procedures are presented. The predictive procedures are based in a family of curves that allows to determine the conducted EMI, generated for the basic PFC converters (boost, buck-boost, Zeta, Sepic, Cuk, and buck converters). Using these curves, one can determine the amplitude of the first harmonic in dB/μV in accordance with the CISPR 16 standard. Therefore, with this information, it is possible to design EMI filter

Modeling views in the layered view model for XML using UML

In data engineering, view formalisms are used to provide flexibility to users and user applications by allowing them to extract and elaborate data from the stored data sources. Conversely, since the introduction of Extensible Markup Language (XML), it is fast emerging as the dominant standard for storing, describing, and interchanging data among various web and heterogeneous data sources. In combination with XML Schema, XML provides rich facilities for defining and constraining user-defined data semantics and properties, a feature that is unique to XML. In this context, it is interesting to investigate traditional database features, such as view models and view design techniques for XML. However, traditional view formalisms are strongly coupled to the data language and its syntax, thus it proves to be a difficult task to support views in the case of semi-structured data models. Therefore, in this paper we propose a Layered View Model (LVM) for XML with conceptual and schemata extensions. Here our work is three-fold; first we propose an approach to separate the implementation and conceptual aspects of the views that provides a clear separation of concerns, thus, allowing analysis and design of views to be separated from their implementation. Secondly, we define representations to express and construct these views at the conceptual level. Thirdly, we define a view transformation methodology for XML views in the LVM, which carries out automated transformation to a view schema and a view query expression in an appropriate query language. Also, to validate and apply the LVM concepts, methods and transformations developed, we propose a view-driven application development framework with the flexibility to develop web and database applications for XML, at varying levels of abstraction

Learning to live together: a challenge for schools located in contexts of social vulnerability

Currently, there are many educational centres that demonstrate the need to promote initiatives to improve coexistence at school at the international level, especially in those located in contexts of social vulnerability. A socio-educational programme has been developed, applied and evaluated at a Singular Education Action Centre (Centro de Acción Educativa Singular - C.A.E.S) in the city of Valencia (Spain). To ascertain the programme's impact and possible generalization to other contexts, a quasi-experimental pretest-posttest design with a control group was used. Information was collected from 297 students and 54 teachers based on questionnaires assessing coexistence at school. The results obtained demonstrate the satisfactory functioning of the programme. The faculty and students from the experimental group affirm the importance of continuing to work in this direction to invest in creating a democratic school that firmly believes in coexistence and participation. Areas for improvement include the need to incorporate actions to increase family participation and develop strategies to facilitate the implementation of a more comprehensive programme

Modular Architecture and Unique Teichoic Acid Recognition Features of Choline-Binding Protein L (CbpL) Contributing to Pneumococcal Pathogenesis

The human pathogen Streptococcus pneumoniae is decorated with a special class of surface-proteins known as choline-binding proteins (CBPs) attached to phosphorylcholine (PCho) moieties from cell-wall teichoic acids. By a combination of X-ray crystallography, NMR, molecular dynamics techniques and in vivo virulence and phagocytosis studies, we provide structural information of choline-binding protein L (CbpL) and demonstrate its impact on pneumococcal pathogenesis and immune evasion. CbpL is a very elongated three-module protein composed of (i) an Excalibur Ca 2+ -binding domain -reported in this work for the very first time-, (ii) an unprecedented anchorage module showing alternate disposition of canonical and non-canonical choline-binding sites that allows vine-like binding of fully-PCho-substituted teichoic acids (with two choline moieties per unit), and (iii) a Ltp-Lipoprotein domain. Our structural and infection assays indicate an important role of the whole multimodular protein allowing both to locate CbpL at specific places on the cell wall and to interact with host components in order to facilitate pneumococcal lung infection and transmigration from nasopharynx to the lungs and blood. CbpL implication in both resistance against killing by phagocytes and pneumococcal pathogenesis further postulate this surface-protein as relevant among the pathogenic arsenal of the pneumococcus.We gratefully acknowledge Karsta Barnekow and Kristine Sievert-Giermann, for technical assistance and Lothar Petruschka for in silico analysis (all Dept. of Genetics, University of Greifswald). We are further grateful to the staff from SLS synchrotron beamline for help in data collection. This work was supported by grants from the Deutsche Forschungsgemeinschaft DFG GRK 1870 (to SH) and the Spanish Ministry of Economy and Competitiveness (BFU2014-59389-P to JAH, CTQ2014-52633-P to MB and SAF2012-39760-C02-02 to FG) and S2010/BMD- 2457 (Community of Madrid to JAH and FG).Peer Reviewe

Contribution of respiratory syncytial virus (RSV) among patients <15 years hospitalized with severe acute respiratory infection (SARI) in Milan, 2014-2017

Aim: Respiratory syncytial virus (RSV) infections may range from cold to severe acute respiratory infection (SARI) and are responsible for substantial pediatric morbidity. We describe the results of RSV molecular detection in respiratory samples collected from children <15 years hospitalized with SARI in Milan (Italy) during four consecutive years. Method: From January 1st, 2014, to December 31st, 2017, 3013 respiratory samples (2826 upper-respiratory-tract [UTR] and 187 lower-respiratory-tract [LTR] specimens) collected from as many children <15 years hospitalized with SARI at an University hospital in Milan were analysed. After DNA/RNA extraction, samples were tested by a multiplex real-time PCR to detect RSV and other respiratory viruses. Results: 571 (19%) respiratory samples tested RSV-positive. RSV-positivity rate by sample type was similar (URT vs LRT: 19.2% vs 14.4%; p=0.09). The median age of RSV-positive cases was 6.6 months (inter-quartile range: 17.2 months); 52.2% were males. 62.2% (355/571) of RSV-positive samples were identified in children <1 year and 12.4% (71/571) in those <1 month. RSV was detected throughout the study period; 59.2% (338/571) cases were identified during seasonal peaks (December-February). In 49.9% (285/571) of RSV-positive samples at least another virus (mainly Rhinovirus: 45.9%) was detected, particularly (60%; 171/285) in samples collected from children >1 year. Conclusions: Accordingly to other studies, RSV was detected in 19% of hospitalized-SARI cases <15 years, mainly in children <1 year and in December-February. Sampling of upper or lower airways resulted in similar RSV-positivity rate. Routine molecular testing to detect RSV is warranted to improve clinical management of pediatric patients

Epidemiological and molecular characteristics of HPEV infection in children<6 months hospitalized with symptoms of sepsie-like illness, northen Italy, 2015-2018

BACKGROUND. Human parechoviruses (HPeVs) are widespread pathogens belonging to the Picornaviridae family and currently divided into 19 genotypes. HPeV infections can be associated with severe clinical manifestations, such as sepsis-like illness, particularly in youngest children. The epidemiological and molecular characteristics of HPeV infections observed in children <6 months hospitalized with symptoms of sepsis-like illness were investigated. METHODS. From January 1st, 2015, to December 31st, 2018, clinical samples (cerebrospinal fluid samples and/or blood samples) were collected for diagnosis of HPeV infection from 193 patients (median age: 21 days, range: 1 day - 6 months) hospitalized with symptoms of sepsis-like illness, in two hospitals of Northern Italy. HPeV-RNA was detected by real-time RT-PCR (target 5\u2019UTR) and a portion of HPeV VP3/VP1 junction (nt. 2159\u20132458) was sequenced for typing and molecular characterization. RESULTS. 14% (27/193) of patients with symptoms of sepsis-like illness tested HPeV-positive. 26/27 (96.3%) HPeV-cases were <3 months and 20/27 (74.1%) <1 month. HPeV-positive cases were detected throughout the study period, mainly (12/27; 44.4%) during the summertime (June-August). 17/27 (63%) HPeV-positive samples were molecularly characterized: 16 resulted HPeV-3 and 1 HPeV-5. CONCLUSIONS. HPeV infection was identified in 14% of children <6 months with symptoms of sepsis-like illness. Almost all HPeV infections were detected in children <3 months and mainly during the summertime; almost all molecularly characterized HPeV belonged to type 3. Including HPeV molecular detection in routine diagnostic tests would allow estimating the burden of HPeV infection and improving clinical management of pediatric patients

Clinical relevance of SARS-CoV-2 infection in late pregnancy

Background: Evidence on the outcome of SARS-CoV-2 infection in pregnancy is generally reassuring but yet not definitive. Methods: To specifically assess the impact of SARS-CoV-2 infection in late pregnancy, we prospectively recruited 315 consecutive women delivering in a referral hospital located in Lombardy, Italy in the early phase of the epidemic. Restriction of the recruitment to this peculiar historical time period allowed to exclude infections occurring early in pregnancy and to limit the recall bias. All recruited subjects underwent a nasopharyngeal swab to assess the presence of Sars-Cov-2 using Real-time PCR. In addition, two different types of antibodies for the virus were evaluated in peripheral blood, those against the spike proteins S1 and S2 of the envelope and those against the nucleoprotein of the nucleocapsid. Women were considered to have had SARS-CoV-2 infection in pregnancy if at least one of the three assessments was positive. Results: Overall, 28 women had a diagnosis of SARS-CoV-2 infection in pregnancy (8.9%). Women diagnosed with the infection were more likely to report one or more episodes of symptoms suggestive for Covid-19 (n = 11, 39.3%) compared to unaffected women (n = 39, 13.6%). The corresponding OR was 4.11 (95%CI: 1.79–9.44). Symptoms significantly associated with Covid-19 in pregnancy included fever, cough, dyspnea and anosmia. Only one woman necessitated intensive care. Pregnancy outcome in women with and without SARS-CoV-2 infection did not also differ. Conclusions: SARS-CoV-2 infection is asymptomatic in three out of five women in late pregnancy and is rarely severe. In addition, pregnancy outcome may not be markedly affected