Quality management systems: relationship between system failure and the reasons for its implementation

Treball final de Grau en Administració d’Empreses. Codi: AE1049. Curs acadèmic 2015-201

Caracterització de la dinàmica de la intrusió marina en base a dades i paràmetres de camp

Salt-water intrusion occurs in coastal freshwater aquifers when the different densities of both, the saltwater and freshwater allow the ocean water to intrude into the freshwater aquifer. This process, despite being a natural process, in recent years has increased its effect as a result of anthropogenic processes, mainly the extraction of groundwater in coastal aquifers. Seawater intrusion is a global issue, exacerbated by increasing demands for freshwater in coastal zones, where the population has increased. One of the most important scientific challenges in the investigation of seawater intrusion is the lack of knowledge on the management of coastal aquifers. Framed within this overall context, the main objective of this project is to deepen in the understanding of the dynamics of the saltwater intrusion in an experimental plot located on the Catalan coast, in order to understand how this dynamic is affected by different parameters: geological, hydrological (rainfall, seasonality, etc.) and coastal (storms, etc.). The results from several field surveys, continuous temporal evolution and geophysical surveys conducted show that seawater mixing zone is located between 15 and 20 meters deep, with horizontal development around 80 meters towards continent, a little further from the well 3. The situation of the mixing zone seems restricted below 12 m depth, just below a siltstone layer, which act as a lower transmissivity zone that hindering hydraulic vertical movement of the transition zone, thus confining the lower aquifer according the transmissivity values obtained in the test pumping. Also there is a low-salinity interface located in the area near the coast. In conclusion, the studied aquifer could be characterized as an aquifer consisting of two zones with different hydraulic behaviours separated by a silt layer. The higher aquifer unit have a behavior of unconfined aquifer and the lower aquifer unit have a semi-confined behaviour, hindering the dynamics of the transition zone with seawater. Conductivity ant temperature data points out the influence of rain and storms in the transition zone location, this influence is different depending on the situation of the piezometer respect to the silt layer.En els aqüífers costaners, les diferencies de densitat permeten que l’aigua marina s’introdueixi sota l’aigua dolça donant lloc a una zona de mescla d’aigua dolça i salada. Aquest procés malgrat ser un procés natural, els darrers anys el seu efecte s’ha incrementat a conseqüència dels processos antropogènics, entre els quals destaca l’extracció d'aigües subterrànies dels aqüífers costaners. La intrusió d’aigua del mar és un problema mundial, degut a la creixent demanda d’aigua dolça a les zones costaneres, en les qual ha augmentat la població. Un dels reptes científics més importants en la investigació de la intrusió marina és la manca de coneixement per la gestió dels aqüífers costers. Dins d’aquest context general, s’emmarca, l’objectiu principal d’aquest treball, el qual pretén aprofundir en el coneixement de la dinàmica de la intrusió marina a escala local a partir d’una parcel·la experimental localitzada a la costa catalana, per tal d’entendre com aquesta dinàmica es veu afectada per diferents variables geològiques, hidrològiques (precipitacions, estacionalitat, etc.) i costaneres (llevantades, etc.). Per estudiar aquesta variabilitat s’utilitzaran dades de nivell piezomètric, conductivitat elèctrica, temperatura i geofísica obtingudes en diversos punts de la zona experimental. Els resultats de les diferents campanyes de camp, de l’evolució temporal realitzada i de les campanyes geofísiques han permès situar la fondària de la zona de mescla d’aigua marina, concretament entre 15 i 20 m de profunditat, amb un desenvolupament horitzontal de fins a 80 metres. La situació de la zona de mescla sembla restringida per sota dels 12 m de fondària, just per sota del nivell de llims, el qual podria actuar com a una zona de menor transmissivitat que dificultaria hidràulicament el moviment vertical de la zona de transició, confinant d’aquesta manera l’aqüífer inferior tal com mostren els valors de les transmissivitats obtingudes en l’assaig de bombeig. També s’observa una interfase salina a menor profunditat situada a la zona propera de la costa. Finalment, a partir de totes les conclusions extretes, l’aqüífer estudiat es podria caracteritzar com un aqüífer constituït per dues zones amb diferents comportaments hidràulics separades per una capa de llims. La unitat aqüífer superior tindria un comportament d’aqüífer lliure i la unitat aqüífer inferior presentaria un comportament de semi-confinat. Les dades de conductivitat i temperatura posen de manifest la influencia de les precipitacions i de les pujades del nivell del mar en la situació de la zona de transició, aquesta influència es diferent en funció de la situació del tram estudiat respecte la cap de llims

Vibrational spectroscopic image analysis of biological material using multivariate curve resolution - alternating least squares

Multivariate data analysis techniques are ideal to decrypt chemical differences between anatomical features or tissue areas in hyperspectral images of biological samples. This protocol provides a user-friendly pipeline and graphical user interface (GUI) for data pre-processing and un-mixing of pixel spectra into their contributing pure components by multivariate curve resolution-alternating least squares (MCR-ALS) analysis. The analysis considers the full spectral profile to identify the chemical compounds and to visualize their distribution across the sample to categorize chemically distinct areas. Results are rapidly achieved (usually less than 30 - 60 min/image) and are easy to interpret and evaluate both in terms of chemistry and biology, making the method generally more powerful than principal component analysis (PCA) or single band intensity heap maps. In addition, chemical and biological evaluation of the results by means of reference matching and segmentation maps (based on k-means clustering) are possible

Symptom-Based Predictive Model of COVID-19 Disease in Children

COVID-19; Microbiology; PaediatricsCOVID-19; Microbiología; PediatríaCOVID-19; Microbiologia; PediatriaBackground: Testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is neither always accessible nor easy to perform in children. We aimed to propose a machine learning model to assess the need for a SARS-CoV-2 test in children (<16 years old), depending on their clinical symptoms. Methods: Epidemiological and clinical data were obtained from the REDCap® registry. Overall, 4434 SARS-CoV-2 tests were performed in symptomatic children between 1 November 2020 and 31 March 2021, 784 were positive (17.68%). We pre-processed the data to be suitable for a machine learning (ML) algorithm, balancing the positive-negative rate and preparing subsets of data by age. We trained several models and chose those with the best performance for each subset. Results: The use of ML demonstrated an AUROC of 0.65 to predict a COVID-19 diagnosis in children. The absence of high-grade fever was the major predictor of COVID-19 in younger children, whereas loss of taste or smell was the most determinant symptom in older children. Conclusions: Although the accuracy of the models was lower than expected, they can be used to provide a diagnosis when epidemiological data on the risk of exposure to COVID-19 is unknown.This research has received external funding from the Fundació la Marató tv3 after being awarded in the COVID-19 research call with the expedient number 202134-30-31

Perception of quality of care of patients with potentially severe diseases evaluated at a distinct quick diagnostic delivery model: a cross-sectional study

Background: Although hospital-based outpatient quick diagnosis units (QDU) are an increasingly recognized cost-effective alternative to hospitalization for the diagnosis of potentially serious diseases, patient perception of their quality of care has not been evaluated well enough. This cross-sectional study analyzed the perceived quality of care of a QDU of a public third-level university hospital in Barcelona. Methods: One hundred sixty-two consecutive patients aged ≥ 18 years attending the QDU over a 9-month period were invited to participate. A validated questionnaire distributed by the QDU attending physician and completed at the end of the first and last QDU visit evaluated perceived quality of care using six subscales. Results: Response rate was 98%. Perceived care in all subscales was high. Waiting times were rated as 'short'/'very short' or 'better'/'much better' than expected by 69-89% of respondents and physical environment as 'better'/'much better' than expected by 94-96 %. As to accessibility, only 3% reported not finding the Unit easily and 7% said that frequent travels to hospital for visits and investigations were uncomfortable. Perception of patient-physician encounter was high, with 90-94% choosing the positive extreme ends of the clinical information and personal interaction subscales items. Mean score of willingness to recommend the Unit using an analogue scale where 0 was 'never' and 10 'without a doubt' was 9.5 (0.70). On multivariate linear regression, age >65 years was an independent predictor of clinical information, personal interaction, and recommendation, while age 18-44 years was associated with lower scores in these subscales. No schooling predicted higher clinical information and recommendation scores, while university education had remarkable negative influence on them. Having ≥4 QDU visits was associated with lower time to diagnosis and recommendation scores and malignancy was a negative predictor of time to diagnosis, clinical information, and recommendation. Discussion: It is worthy of note that the questionnaire evaluated patient perception and opinions of healthcare quality including recommendation rather than simply satisfaction. It has been argued that perception of quality of care is a more valuable approach than satisfaction. In addition to embracing an affective dimension, satisfaction appears more dependent on patient expectations than is perception of quality. Conclusions: While appreciating that completing the questionnaire immediately after the visit and its distribution by the QDU physician may have affected the results, scores of perceived quality of care including recommendation were high. There were, however, significant differences in several subscales associated with age, education, number of QDU visits, and diagnosis of malignant vs. benign condition

Resolució multivariant en Química: a la cerca de la bella simplicitat de la mesura

En Quimiometria, existeix una família de mètodes, coneguts sota la denominació comuna de resolució multivariant, que permeten descriure fenòmens molt complexos i diversos a partir de la combinació de poques contribucions bàsiques fàcilment interpretables. La versatilitat i simplicitat dels models de resolució multivariant ha fet que s'hagin aplicat amb èxit en el modelatge de processos d'origen químic i bioquímic i en la interpretació de dades -òmiques i ambientals

Age-dependency of the propagation rate of coronavirus disease 2019 inside school bubble groups in Catalonia, Spain

We analyzed contagions of coronavirus disease 2019 inside school bubble groups in Catalonia, Spain, in the presence of strong nonpharmaceutical interventions from September to December 2020. More than 1 million students were organized in bubble groups and monitored and analyzed by the Health and the Educational departmentPostprint (published version

A randomized phase II study of capecitabine-based chemoradiation with or without bevacizumab in resectable locally advanced rectal cancer: clinical and biological features

Background: perioperatory chemoradiotherapy (CRT) improves local control and survival in patients with locally advanced rectal cancer (LARC). The objective of the current study was to evaluate the addition of bevacizumab (BEV) to preoperative capecitabine (CAP)-based CRT in LARC, and to explore biomarkers for downstaging. Methods: patients (pts) were randomized to receive 5 weeks of radiotherapy 45 Gy/25 fractions with concurrent CAP 825 mg/m2 twice daily 5 days per week and BEV 5 mg/kg once every 2 weeks (3 doses) (arm A), or the same schedule without BEV (arm B). The primary end point was pathologic complete response (ypCR: ypT0N0). Results: ninety pts were included in arm A (44) or arm B (46). Grade 3-4 treatment-related toxicity rates were 16% and 13%, respectively. All patients but one (arm A) proceeded to surgery. The ypCR rate was 16% in arm A and 11% in arm B (p =0.54). Fifty-nine percent vs 39% of pts achieved T-downstaging (arm A vs arm B; p =0.04). Serial samples for biomarker analyses were obtained for 50 out of 90 randomized pts (arm A/B: 22/28). Plasma angiopoietin-2 (Ang-2) levels decreased in arm A and increased in arm B (p <0.05 at all time points). Decrease in Ang-2 levels from baseline to day 57 was significantly associated with tumor downstaging (p =0.02). Conclusions: the addition of BEV to CAP-based preoperative CRT has shown to be feasible in LARC. The association between decreasing Ang-2 levels and tumor downstaging should be further validated in customized studies

Symptom-based predictive model of COVID-19 disease in children

Testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is neither always accessible nor easy to perform in children. We aimed to propose a machine learning model to assess the need for a SARS-CoV-2 test in children (<16 years old), depending on their clinical symptoms. Methods: Epidemiological and clinical data were obtained from the REDCap® registry. Overall, 4434 SARS-CoV-2 tests were performed in symptomatic children between 1 November 2020 and 31 March 2021, 784 were positive (17.68%). We pre-processed the data to be suitable for a machine learning (ML) algorithm, balancing the positive-negative rate and preparing subsets of data by ageThis research has received external funding from the Fundació la Marató tv3 after being awarded in the COVID-19 research call with the expedient number 202134-30-31.Objectius de Desenvolupament Sostenible::3 - Salut i BenestarPostprint (published version