Management systems: integration or addition?

Purpose – In the past few years, management systems implementation and certification has become a common practice among different types of organizations. In this context, quality management systems certification, according to the ISO 9001 standard is in the spotlight, due to over than 1.000.000 certified organizations by the end of 2009. Quality management systems can be integrated with an increasing variety of other subsystems implemented according to other standards, including environmental systems, health and safety, social responsibility, R&D, risk, or human resources, and subsystems raised from specific standards designed for specific activity sectors (HACCP, automotive or aeronautics, medical devices, pharmaceuticals and software). Due to this evolution, careful attention should be taken on how these different subsystems have been and should be articulated, harmonized and integrated. Thus, this paper intends to approach different strategies to achieve integration, with several levels of intensity, depth and authenticity between the different subsystems, and report some final recommendations related with good practices assuring the efficiency and effectiveness of the integration process. Design/methodology/approach – A case study methodology has supported this research. Three case studies were conducted on Portuguese companies that have an integrated quality, environmental and safety management system. Findings – If the companies’ strategy is to implement more than one management system, there is a clear advantage of doing it supported on an integrated approach, avoiding the development of organizational “islands” related to each subsystem. This organizational “archipelago” structure is completely far way from any global optimized solution, based on a holistic perspective. Originality/value – Based on the conclusions that we were able to find out, this paper is an important contribution to the integrated management systems research area, because it states different integration approaches and levels

Prognostic prediction models using Self-Attention for ICU patients developing acute kidney injury

Tese de mestrado, Ciência de Dados, Universidade de Lisboa, Faculdade de Ciências, 2022The general growth and improved accessibility to electronic health records demands an identical level of progress in terms of the research community regarding clinical models. The usage of machine learning techniques is key to this development, and so they are increasingly being used in large medical databases with the purpose of creating solutions that work for specified patients, no matter the task or the disease. Acute kidney injury (AKI) is a broad disease defined by abrupt changes in renal function. AKI has a high morbidity and mortality, with an increased focus on critically ill patients. The main goal of this thesis is to study the development of AKI within a patient’s stay in the intensive care unit (ICU). Data from the MIMIC-III database was used to collect information regarding the patients. After a detailed exclusion criteria, those were evaluated in terms of AKI stages, with the purpose of predicting the next value of AKI stage one hour after the sequence of information fed to the model. This can suggest the capacity of the model at predicting the aggravation of a patient’s AKI condition. The sequences used have hourly information for every feature, and were used sequences of 6h, 12h and 24h length. Self-attention mechanisms were used to make the predictions, using an adaptation for multi-variate time series built from the successfully used models on natural language processing (NLP) tasks. The predictions on this work were made for two variations of the KDIGO classification system: one where only the serum creatinine (SCr) criteria was taken into account to determine the patient’s AKI stage, and other where both SCr and urine output (UO) were considered. While most works addressing AKI only tend to use SCr values to determine the patient’s AKI condition, the results were compared using both approaches and were better when using both SCr and UO. For those experiments, the model achieved up to 68.05% accuracy predicting an episode of AKI, compared to the 66.67% accuracy achieved using only SCr values, which outperformed state-of-the-art results for both cases. Feature importance was also used for each dataset associated with the two variations of KDIGO classification system to identify what were the most important features. Furthermore, final results were compared when using all features versus only using the most 10 important ones

Comunidades intertidais e subtidais de trematodes: influência dos fatores ambientais na infeção de berbigões

Cerastoderma edule, the edible cockle, is a dominant and widely distributed bivalve of the northeast Atlantic coast. This bivalve is a highly exploited species in many countries, displaying an important socio-economic role and playing crucial services for ecosystem functioning. This bivalve is host of several trematode species, the most prevalent clade of macroparasites in coastal waters, that display a complex life cycle commonly including three host species. Trematodes are able to modulate cockles population dynamics, exerting devastating impacts depending on abundance, life-cycle stage or combination with abiotic factors. However, the patterns by which they govern are still poorly understood. The present thesis aimed to recognize environmental patterns that could regulate trematode population dynamics, identifying the major factors implicated in infection rate variability. In the first instance, an extensive spatial sampling of cockles was performed from north Portugal to south Morocco in order to identify large scale drivers of parasite community structure and to analyse, for the first time, cockles south of 31 °N. Most of the 12 identified trematode species were observed along the whole latitudinal gradient demonstrating the high dispersal ability of these parasites. Results suggested that temperature was the most important trigger to predict parasite infection, with coastal upwelling system operating for Portugal as a shield against trematode infection. Nonetheless, hosts geographical distribution, second intermediate host tidal position and the oceanic influence also seemed to affect trematode abundance. Following these results, the effect of host vertical position (intertidal vs. subtidal) and hydrodynamics on trematode infection rate was assessed at a small-scale. For this, cockles were collected in intertidal and subtidal sites of downstream and upstream areas of the Ria de Aveiro coastal lagoon (Portugal). Cockle density, trematode infection and sediment and water physico-chemical features were assessed. To characterize the lagoon hydrodynamics, simulation with the numerical model Mohid were performed. Intertidal cockles displayed significantly higher individual infection than those from subtidal sites, highlighting that the host vertical position represent an important driver of trematode infection success, possibly due to shorted distance from the first intermediate host (often intertidal gastropods) or lower capacity of cercariae (trematode free-living stage emerging from the first intermediate host to infect second intermediate host) to find their suitable host in a subtidal environment and then to complete the life cycle. Overall, the downstream areas (= higher hydrodynamics) presented higher trematode abundance suggesting a positive influence of water dynamics in the ecological quality of these areas, increasing the dispersion of trematode freeliving stages that promotes contact with the second intermediate host and consequent infection success. The influence of water current on trematodes infection was corroborated through experimental approach. Lastly, and pursuing the track of some of the obtained results (namely the infection between intertidal and subtidal sites), the effect of light on cercariae transmission success, using the trematode Himasthla elongata was assessed. Through experimental approach, this study aimed to observe the influence of light (no light vs. light exposure) on the cercariae behaviour. Nevertheless, cockles under dark conditions presented higher levels of infection compared to cockles exposed to light. These differences were explained by the influence of light on the cercariae swimming activity, which navigation showed to be guided by the light position and not by the presence and/ or filtering capacity, since that cockles respiration rate was similar regardless light conditions. This thesis findings demonstrated the importance of abiotic factors on the transmission success of trematode parasites. The outcomes of this study can be used for a more efficient management of cockles stocks by helping to predict areas or periods of higher probability of a trematode abundance outbreak.O berbigão, Cerastoderma edule, é uma espécie de bivalve amplamente distribuída pela costa nordeste do Atlântico. Este bivalve é altamente explorado em vários países, inclusive Portugal, tendo uma alta relevância socioeconómica e um papel importante em serviços cruciais para o funcionamento do ecossistema. Este bivalve é hospedeiro de várias espécies de trematodes, os macroparasitas mais prevalentes em águas costeiras, que exibem um ciclo de vida complexo e que geralmente usam três espécies diferentes de hospedeiros. Os trematodes são capazes de modular a dinâmica populacional dos berbigões, exercendo sobre eles impactos devastadores dependendo da abundância, fase do ciclo de vida ou da combinação com fatores abióticos. No entanto, os padrões pelos quais estes parasitas se governam ainda são pouco compreendidos. Assim, esta tese teve como objetivo principal, reconhecer padrões ambientais que podem regular a população de trematodes, identificando os principais fatores implicados na variabilidade da taxa de infeção. Num primeiro momento, foi realizada uma extensa amostragem espacial de berbigão, desde o norte de Portugal até ao sul de Marrocos, de forma a identificar fatores que influenciam, em larga escala, a comunidade dos parasitas e que permitiu analisar, pela primeira vez, berbigões a sul de 31 °N. Das 12 espécies de trematodes identificadas, várias foram observadas em todo o gradiente latitudinal demonstrando a grande capacidade de dispersão destes parasitas. Os resultados sugeriram que a temperatura foi o fator mais importante para despoletar a infeção por trematodes, com o sistema de upwelling da costa Portuguesa a funcionar como proteção contra a infeção por trematodes. No entanto, a distribuição geográfica dos hospedeiros, a posição de maré do segundo hospedeiro e a influência oceânica também pareceram ter efeito na abundância dos trematodes. No seguimento destes resultados, avaliou-se os efeitos, em pequena escala, da posição vertical (intertidal ou subtidal) e do hidrodinamismo na taxa de infeção por trematodes. Para isso, foi recolhido berbigão em zonas intertidais e subtidais de uma área a montante e a jusante da Ria de Aveiro. Foram analisados a densidade de berbigão, a infeção por trematodes e os parâmetros físicoquímicos do sedimento e da água. Para caracterizar o hidrodinamismo da Ria procedeu-se a várias simulações através do modelo Mohid. Berbigão da zona intertidal demonstrou maiores níveis de infeção, destacando a importância da posição vertical do hospedeiro no sucesso da infeção pelos trematodes, possivelmente devido a uma distância mais curta ao primeiro hospedeiro (geralmente gastrópodes intertidais) ou a uma menor capacidade das cercariae (estado de vida livre dos trematodes que emerge do primeiro hospedeiro e infeta o segundo) para encontrar o seu hospedeiro num ambiente subtidal e completar o ciclo de vida. No geral, as áreas a jusante (maior hidrodinamismo) apresentaram níveis de infeção mais altos, sugerindo uma influência positiva da dinâmica da água na qualidade ecológica destes habitats, aumentando a dispersão das cercariae promovendo, desta forma, o contacto com os seus hospedeiros e consequentemente, aumentando o sucesso da infeção. A influência da corrente da água na infeção de trematodes foi corroborada por uma experiência laboratorial. Por último, e seguindo alguns dos resultados obtidos (principalmente a diferença de infeção entre a zona intertidal e subtidal), foi testado o efeito da luz no sucesso da transmissão pela cercaria da espécie de trematode Himasthla elongata. Através duma experiência laboratorial, pretendeu-se observar o efeito da luz (ausência vs. presença de luz) no comportamento das cercariae. Berbigões sob a ausência de luz demonstraram ficar mais parasitados do que os que se encontravam expostos à luz. As diferenças foram explicadas pela influência da luz na atividade natatória das cercariae e não pela presença ou capacidade filtradora dos berbigões, uma vez que, estes não demonstraram diferenças na taxa de respiração, qualquer que fosse a exposição luminosa. Esta tese demonstrou a importância dos fatores abióticos no sucesso de transmissão dos trematodes entre hospedeiros. Os resultados deste estudo podem ser utilizados de modo a controlar e a melhor gerir as populações de berbigão, ajudando a prever áreas ou períodos de maior probabilidade de surtos de abundância de trematodes.Mestrado em Biologia Aplicad

Iontronics with cork

This work reports an unprecedented functionalization of one of the most unique natural materials on Earth, cork, in the field of electronics. Motivated by the excessive waste of the cork industry and resorting to other natural and abundant materials in nature, it was possible to successfully develop electrolytes based on cork. In a primary approach, there are several steps considered and constantly reevaluated in order to produce the first functional cork-based electrolyte. An aqueous lithium salts and urea solvent system is essential, as well as a natural binding agent, herein a cellulose derivative, and an acid neutralization. Secondly, these novel cork-based electrolytes are put to the test as the gate dielectric on EGTs with a cellulose based semiconducting ink, and their electrical performance is studied. The cork-based electrolytes show interesting properties for applications such as supercapacitors, electronic wearables or electrochromic displays due to their electrical double-layer capacitance (CDL) values of more than 8 μF cm−2 and ionic conductivity in the order of 10−4 S cm−1. Carboxymethyl cellulose and zinc oxide EGTs on cork composite substrates with the functional cork material as the gate dielectric exhibit low working voltage (<2 V), Ion/Ioff ratios of 103, a subthreshold swing (SS) lower than 0.3 Vdec−1, low saturation mobilities (SAT) at 0.4 cm2V−1s−1 and transconductance (gm) of 10−6 S. The flexible corkbased electrolyte-gated transistors on paper are also demonstrated, operating at low voltage (Von <1V) and exhibiting transconductance (gm) values of 10−4 S and saturation mobilities (SAT) higher than 10 cm2V−1s−1

Organossílicas com mesoporosidade para aplicação em pilhas de combustível

The objective of this thesis is to assess the potential of acid-functionalized periodic mesoporous organosilicas (Ph-PMO) as fillers for the polymer membrane in polymer electrolyte fuel cells, aiming at improved performance under low relative humidity (r.h.120 °C) operation conditions. Ph-PMOs mimic the structure of Nafion®, presenting a similar acid load distributed on pores with similar width (3 nm) and with similar distance between acid sites (0.8 nm), but on a stable, rigid structure preventing the proton confinement to the pore surface that occurs in Nafion®. This offers potentially high protonic conductivity under dry conditions, in addition to improved visco-elastic behaviour. Two protogenic groups based on sulfonic (S-Ph-PMO) and phosphonic (P-Ph-PMO) acids were used to functionalize Ph-PMOs with variable structural and microstructural features. The conductivity of both types of Ph-PMOs increases with increasing specific surface area and r.h., confirming the surface nature of the protonic transport and the key role of the hydration water on the protonic transport. The strongest acid character of S-Ph-PMOs leads to a much higher conductivity, attaining values of up to ~0.1 S∙cm-1 at 94 °C and 98% r.h. Results obtained for a series of S-Ph-PMO samples with variable acid loadings, surface area and structural order, prepared by a microwave hydrothermal reaction, show that the conductivity increases with increasing acid loading, whereas no clear correlation can be established with structural order parameters. S-Ph-PMOs were selected for the preparation of composite Nafion® membranes and their transport and visco-elastic properties evaluated. The bulk effect of the fillers is demonstrated by a 10 fold increase of the storage modulus (E’) at 140 °C of composite membranes with up to 36 vol.% S-Ph-PMO, in comparison with pure Nafion®. The effect of fillers on the bulk properties is also apparent on the swelling under saturated conditions, which is reduced by 30% with addition of 36 vol.% of fillers, indicating virtually zero swelling of the fillers. These improvements may be crucial to increase the thermo-mechanical stability of the membrane and of the electrode/electrolyte interface. The conductivity of the composite membranes is less dependent on r.h. and temperature, and can be up to 1 order of magnitude higher than for pure Nafion®, at 20% r.h. and 40 °C. Differences are smaller at high r.h., with the highest conductivity of 0.2 S∙cm-1 achieved at 94 °C and 98% r.h. However, and as opposed to the bulk effects on E’ and swelling, a conductivity maximum is observed for the membranes with 20 vol.% of fillers. The use of different fillers in a series of 20 vol.% composite membranes showed that there is a slight increase of the membrane conductivity with increasing acid load and surface area of the fillers, however no direct correlation could be drawn for the structural properties. The increased conductivity at low r.h. can be interpreted considering a reduction of the proton confinement in the rigid pores of the fillers and, as the r.h. increases, by assuming a surface effect, where the presence of the mesoporous fillers disrupts the “skin-like” structure that forms at the surface of Nafion®, releasing the internal pressure and hence facilitating the access of the hydration water to the bulk of the membrane.O objectivo desta dissertação é o de avaliar o potencial de organossílicas mesoporosas periódicas (Ph-PMO) como aditivos para membranas poliméricas de pilhas de combustível, visando um melhor desempenho a baixa humidade relativa (h.r. 120 ºC). A estrutura dos Ph-PMO mimetiza a do Nafion®, apresentando semelhante tamanho de poro (3 nm) e distância entre grupos ácido (0.8 nm), mas com uma estrutura estável e rígida que reduz o efeito de confinamento protónico à superfície do poro, que ocorre no Nafion®. Este efeito pode potencialmente traduzir-se num aumento da condutividade protónica em condições anidras, para além de melhorar o comportamento visco-elástico. Foram sintetizados Ph-PMO com grupos ácido sulfónico (S-Ph-PMO) e ácido fosfónico (P-Ph-PMO), com características estruturais e microestruturais distintas. A condutividade dos dois tipos de Ph-PMO aumenta com o aumento da área superficial específica e da h.r., confirmando o papel central da superfície e da água de hidratação no transporte protónico. A maior acidez dos S-Ph-PMO resulta em valores de condutividade superiores, da ordem de 0.1 S∙cm-1 a 94 ºC e 98% de h.r. Os resultados obtidos com uma série de S-Ph-PMO com diferentes concentrações de grupos funcionais, área superficial específica e ordem estrutural, preparados por reacção hidrotermal em micro-ondas, mostram que a condutividade aumenta com o aumento da concentração de grupos ácidos, não sendo, no entanto, correlacionável com a ordem estrutural. Foram seleccionadas várias amostras de S-Ph-PMO para preparar membranas compósitas à base de Nafion®, avaliando as suas propriedades visco-elásticas e de transporte protónico. Para a membrana com cerca de 36 vol.% de aditivos, o efeito de volume dos aditivos é evidenciado por um módulo de armazenamento (E’) até 10 vezes superior ao do Nafion® puro. O efeito dos aditivos faz-se também sentir na diminuição da dilatação das membranas por absorção de água até 30%, devido à dilatação virtualmente nula dos aditivos. O aumento do E’ e diminuição da dilatação podem vir a ser cruciais para a melhoria da estabilidade termo-mecânica das membranas e da interface eléctrodo/electrólito. A condutividade das membranas compósitas é menos dependente da h.r. e da T, podendo ser até 1 ordem de grandeza superior à condutividade do Nafion® puro a 40 ºC e 20% de h.r. As diferenças são menos significativas a alta h.r., atingindo o valor máximo de 0.2 S∙cm-1 a 94 ºC e 98 % h.r. No entanto, contrariamente ao efeito de volume no E’ e na dilatação, a condutividade máxima foi atingida numa membrana com 20 vol.% de aditivos. Verifica-se que a condutividade das membranas tende a aumentar ligeiramente com o aumento da área superficial e da concentração de grupos ácido dos aditivos, sendo o efeito da ordem estrutural muito pouco visível. O aumento da condutividade das membranas compósitas, a baixa h.r., pode ser interpretado considerando a redução do confinamento protónico e, à medida que a h.r. aumenta, assumindo um efeito de superfície, no qual a presença dos aditivos provoca a ruptura de uma estrutura rígida que se forma à superfície da membrana de Nafion®, libertando a pressão interna e facilitando o acesso da água ao interior da membrana e desse modo aumentando a condutividade.Programa Doutoral em Ciência e Engenharia de Materiai

A brief journey along time in the Guadiana estuary

The physical characteristics of the Guadiana estuary and the richness of its adjacent territories were essential in defining the historical and cultural context of the entire region. The extended navigability of the estuary was fundamental to establish trade routes with the Mediterranean civilizations, namely with the Phoenicians, Greeks, and Carthaginians. These civilizations created several commercial harbors along the Guadiana, namely in Mértola, Alcoutim, Castro Marim and Ayamonte. In these locations the human presence dates back as far as the Neolithic (12,000 to 4,000 BCE) and the Chalcolithic periods (4,000 to 3,100 BCE). Later, the Romans (II BCE to V CE), the Alans (V to VI CE.), the Visigoths (VI to VIII CE), and the Arabs (VIII to XIII CE) successively settled in this Iberian region, until the borders of the continental Portuguese territory were set in the 13th century. The predominant North-South direction of the estuary is intrinsically linked with the definition of the Portuguese and Spanish territories, as it serves as a natural border in its last 50 km. Ore extraction and cereal production in the surrounding areas of the estuary turned Mértola into the most important trading center, up to the Portuguese conquest in 1238 (Fig. 6.1). Copper, iron, and manganese were the main ore resources, but silver and gold were exploited as well. With the Portuguese conquests, the economic importance of the Guadiana estuary decreased sharply. In the 15th and 16th centuries, cereals were shipped to the Portuguese forts of northern Africa, but it was only in the late 19th century that all the regions around the estuary had a new economic burst.info:eu-repo/semantics/publishedVersio

Barómetro da Certificação 2014

info:eu-repo/semantics/publishedVersio

Different perspectives on management systems integration

Increasingly competitive economies and the market globalisation process have led many organisations to implement management systems as a differential against competition. However, with the variety of standards available, they felt the need to integrate management subsystems aiming at resources and skills optimisation, in order to achieve performance maximisation of the resulting integrated management system (IMS). Added to this, it is known that the value of a single certificate is inversely proportional to the overall increase in certificate numbers. This paper intends to report the study results focusing on critical success factors (CSFs) assessment, difficulties faced by organisations when implementing an IMS, and the resulting benefits. Additionally, the quantitative evolution of IMS in Portuguese companies until 2011 is reported, showing how IMS typologies evolved and increased their relative ‘weight’ among Portuguese certified companies. Related to the study, the sample was composed of four Portuguese IMS ruled organisations based on quality, environment and occupational health and safety certified management subsystems. The data collection methodology was based on semistructured interviews with the management system manager, through which it was sought to analyse the entire integration process. Results suggest that management subsystems integration contributes positively to the studied organisations. Top management involvement, human and financial resources availability and training were identified as subsystems integration CSF. Among the difficulties faced by organisations they pointed out the non existence of a previous organisational structure and the employees’ behaviour changes

Nucleic acid derived indices or instantaneous growth rate as tools to determine different nutricional condition in cuttlefish (Sepia officinalis, linnaeus 1758) hatchlings

Two groups of 100 cuttlefish hatchlings each were used to determine the duration of the yolk reserves, during which growth can be obtained with no food supply. One group was fed live grass shrimp ad libitum from the 3rd day of life onwards, while the other was starved during the whole experiment. The experiment lasted 7 days, because this was the 1st day where a negative growth rate was obtained. Nucleic acid derived indices and instantaneous growth rates (IGR) were used as a way to describe their condition, when all the yolk reserves would be exhausted and to determine the most accurate tool to express growth and condition. RNA/DNA ratios described clearly the differences (P 0.05) between groups and did not displayed a clear pattern with increasing age. Correlation between IGR and DNA was only attained for the fed population (R −0.90; P 0.0374). RNA concentration values were different from day 5 onwards. Any of the nucleic acid derived indexes were not accurate enough to express growth and condition, so IGR seems to be the most accurate and inexpensive way to describe hatchlings growth and condition in controlled conditions.info:eu-repo/semantics/publishedVersio