Machine learning for iron oxide identification from oxygen K edge in EELS spectra

Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2021, Tutors: Sònia Estradé, Daniel Del Pozo BuenoIn this work we test machine learning tools such as the Support Vector Machine algorithm and neural network models on the task of Electron Energy-Loss Spectroscopy (EELS) spectra classification. Given many sample spectra of EELS applied on wüstite and magnetite nanocubes, we train both models to determine the oxidation state of iron. We show that SMV exhibits a good performance on classifying clean data, and we demonstrate the capability of neural networks of producing robust results given shifted dat

Underwater seismometer validation

This work verifies and validates the calibration in a marine geophone by means of a hyperbaric chamber before and after the pressure underwater laboratory test. The objective is to characterise the transfer function according to the frequency of coupling between the geophone and the sediment. It is possible to observe the geophone coupling variations through the sediment after the test inside the water pressure at the equivalent of 200 metres depth.Peer Reviewe

Underwater seismometer validation

This work verifies and validates the calibration in a marine geophone by means of a hyperbaric chamber before and after the pressure underwater laboratory test. The objective is to characterise the transfer function according to the frequency of coupling between the geophone and the sediment. It is possible to observe the geophone coupling variations through the sediment after the test inside the water pressure at the equivalent of 200 metres depth.Peer ReviewedPostprint (published version

Effectiveness and safety of vedolizumab induction with or without budesonide in patients with moderately to severely active Crohn's disease in Europe: a retrospective observational study

BACKGROUND Vedolizumab (VDZ), a gut-selective anti-lymphocyte trafficking integrin antibody, is effective in treating patients with moderately to severely active Crohn's disease (CD). In this study, we examined the real-world effectiveness and safety of induction therapy using VDZ alone or in combination with budesonide (VDZ + BUD) among patients with CD in Belgium, Israel, and Switzerland. METHODS This retrospective chart review analysis included adult patients with moderately to severely active CD who started induction treatment with VDZ or VDZ + BUD (January 2015 through January 2019). The primary objective of this study was to assess the effectiveness in terms of clinical remission of VDZ alone or VDZ + BUD using patient-reported outcomes (PRO) of abdominal pain (AP) and/or loose stool frequency (LSF) (PRO-2) at weeks 0, 2, 6, 10, and 14. Regression models were used to assess differences and associations between the treatment groups. RESULTS Overall, 123 patients were included (VDZ, n = 73; VDZ + BUD, n = 50). Clinical remission rates at week 14 were 71.4% (50/70) and 68.0% (34/50) with VDZ and VDZ + BUD, respectively. Mean percentage change in AP and LSF from baseline to week 14 was comparable between the groups. Median (95% confidence interval [CI]) time to clinical remission was 91 [70.0-98.0] and 95 [70.0-98.0] days, respectively. One patient in each group discontinued VDZ and 68.0% of patients in the VDZ + BUD group discontinued BUD before week 14. The rates of overall adverse events were similar between the groups (VDZ, 23.3%; VDZ + BUD, 26.0%). CONCLUSIONS In this retrospective study, VDZ alone and VDZ + BUD showed similar high remission rates in patients with moderately to severely active CD. Prospective randomized studies are needed to conclude on the role of combining VDZ with BUD. TRIAL REGISTRATION Not applicable

Characteristics of COPD patients initiating treatment with aclidinium or tiotropium in primary care in Catalonia : a population-based study

To describe and compare demographic and clinical profile of patients newly initiated on aclidinium (ACL) or tiotropium (TIO) and identify factors associated with newly initiated ACL in real-life clinical practice during 2013 in Catalonia. We performed a population-based, retrospective, observational study with data obtained from the Information System for Research Development in Primary Care, a population database that contains information of 5.8 million inhabitants (more than 80% of the Catalan population). Patients over 40 years old, with a recorded diagnosis of COPD and newly initiated treatment with either ACL or TIO during the study period (January to December 2013), were selected. A descriptive analysis of demographic and clinical characteristics was performed, and treatment adherence was also assessed for both cohorts. A total of 8,863 individuals were identified, 4,293 initiated with ACL and 4,570 with TIO. They had a mean age of 69.4 years (standard deviation: 11.3), a median COPD duration of 3 years (interquartile range: 0-8), and 71% were males. Patients treated with ACL were older, with more respiratory comorbidities, a longer time since COPD diagnosis, worse forced expiratory volume in 1 second (% predicted), and with a higher rate of exacerbations during the previous year compared with TIO. It was found that 41.3% of patients with ACL and 62.3% of patients with TIO had no previous COPD treatment. Inhaled corticosteroid and long-acting β2-agonist were the most frequent concomitant medications (32.9% and 32.6%, respectively). Approximately 75% of patients were persistent with ACL or TIO at 3 months from the beginning of treatment, and more than 50% of patients remained persistent at 9 months. Patients initiated with ACL had more severe COPD and were taking more concomitant respiratory medications than patients initiated with TIO. ACL was more frequently initiated as part of triple therapy, while TIO was more frequently initiated as monotherapy

Experiences of Mining Engineering students in cooperation for development

Peer ReviewedObjectius de Desenvolupament Sostenible::3 - Salut i BenestarObjectius de Desenvolupament Sostenible::8 - Treball Decent i Creixement EconòmicObjectius de Desenvolupament Sostenible::13 - Acció per al ClimaObjectius de Desenvolupament Sostenible::17 - Aliança per a Aconseguir els ObjetiusPostprint (published version

Eliciting health state utilities for Dupuytren's contracture using a discrete choice experiment

Background and purpose An internet-based discrete choice experiment (DCE) was conducted to elicit preferences for a wide range of Dupuytren’s contracture (DC)-related health states. An algorithm was subsequently developed to convert these preferences into health state utilities that can be used to assess DC’s impact on quality of life and the value of its treatments. Methods Health state preferences for varying levels of DC hand severity were elicited via an internet survey from a sample of the UK adult population. Severity levels were deined using a combination of contractures (0, 45, or 90 degrees) in 8 proximal interphalangeal and metacarpophalangeal joints of the index, middle, ring, and little ingers. Right-handed, left-handed, and ambidextrous respondents indicated which hand was preferable in each of the 10 randomly-selected hand-pairings comparing different DC severity levels. For consistency across comparisons, anatomically precise digital hand drawings were used. To anchor preferences onto the traditional 0–1 utility scale used in health economic evaluations, unaffected hands were assigned a utility of 1.0 whereas the utility for a maximally affected hand (i.e., all 8 joints set at 90 degrees of contracture) was derived by asking respondents to indicate what combination of attributes and levels of the EQ-5D-5L proile most accurately relects the impact of living with such hand. Conditional logistic models were used to estimate indirect utilities, then rescaled to the anchor points on the EQ-5D-5L. Results Estimated utilities based on the responses of 1,745 qualiied respondents were 0.49, 0.57, and 0.63 for completely affected dominant hands, non-dominant hands, or ambidextrous hands, respectively. Utility for a dominant hand with 90-degree contracture in t h e metacarpophalangeal joints of the ring and little ingers was estimated to be 0.89. Separately, reducing the contracture of metacarpophalangeal joint for a little inger from 50 to 12 degrees would improve utility by 0.02. Interpretation DC is associated with substantial utility decrements. The algorithms presented herein provide a robust and lexible framework to assess utility for varying degrees of DC severity

Longitudinal estimation of Plasmodium falciparum prevalence in relation to malaria prevention measures in six sub-Saharan African countries.

BACKGROUND: Plasmodium falciparum prevalence (PfPR) is a widely used metric for assessing malaria transmission intensity. This study was carried out concurrently with the RTS,S/AS01 candidate malaria vaccine Phase III trial and estimated PfPR over ≤ 4 standardized cross-sectional surveys. METHODS: This epidemiology study (NCT01190202) was conducted in 8 sites from 6 countries (Burkina Faso, Gabon, Ghana, Kenya, Malawi, and Tanzania), between March 2011 and December 2013. Participants were enrolled in a 2:1:1 ratio according to age category: 6 months-4 years, 5-19 years, and ≥ 20 years, respectively, per year and per centre. All sites carried out surveys 1-3 while survey 4 was conducted only in 3 sites. Surveys were usually performed during the peak malaria parasite transmission season, in one home visit, when medical history and malaria risk factors/prevention measures were collected, and a blood sample taken for rapid diagnostic test, microscopy, and haemoglobin measurement. PfPR was estimated by site and age category. RESULTS: Overall, 6401 (survey 1), 6411 (survey 2), 6400 (survey 3), and 2399 (survey 4) individuals were included in the analyses. In the 6 months-4 years age group, the lowest prevalence (assessed using microscopy) was observed in 2 Tanzanian centres (4.6% for Korogwe and 9.95% for Bagamoyo) and Lambaréné, Gabon (6.0%), while the highest PfPR was recorded for Nanoro, Burkina Faso (52.5%). PfPR significantly decreased over the 3 years in Agogo (Ghana), Kombewa (Kenya), Lilongwe (Malawi), and Bagamoyo (Tanzania), and a trend for increased PfPR was observed over the 4 surveys for Kintampo, Ghana. Over the 4 surveys, for all sites, PfPR was predominantly higher in the 5-19 years group than in the other age categories. Occurrence of fever and anaemia was associated with high P. falciparum parasitaemia. Univariate analyses showed a significant association of anti-malarial treatment in 4 surveys (odds ratios [ORs]: 0.52, 0.52, 0.68, 0.41) and bed net use in 2 surveys (ORs: 0.63, 0.68, 1.03, 1.78) with lower risk of malaria infection. CONCLUSION: Local PfPR differed substantially between sites and age groups. In children 6 months-4 years old, a significant decrease in prevalence over the 3 years was observed in 4 out of the 8 study sites. Trial registration Clinical Trials.gov identifier: NCT01190202:NCT. GSK Study ID numbers: 114001

Underwater seismometer validation

This work verifies and validates the calibration in a marine geophone by means of a hyperbaric chamber before and after the pressure underwater laboratory test. The objective is to characterise the transfer function according to the frequency of coupling between the geophone and the sediment. It is possible to observe the geophone coupling variations through the sediment after the test inside the water pressure at the equivalent of 200 metres depth.Peer Reviewe