8 resultados para EVALUATION MODEL
em RUN (Repositório da Universidade Nova de Lisboa) - FCT (Faculdade de Cienecias e Technologia), Universidade Nova de Lisboa (UNL), Portugal
Resumo:
On a mobile ad-hoc network environment, where the resources are scarce, the knowledge about the network's link state is essential to optimize the routing procedures. This paper presents a study about different pheromone evaluation models and how they react to possible changes in traffic rate. Observing how the pheromone value on a link changes, it could be possible to identify certain patterns which can indicate the path status. For this study, the behavior of the Ant System evaluation model was compared with a Temporal Active Pheromone model (a biological approach) and a Progressive Pheromone Reduction model with and without a maximum pheromone limit.
Resumo:
Water is a limited resource for which demand is growing. Contaminated water from inadequate wastewater treatment provides one of the greatest health challenges as it restricts development and increases poverty in emerging and developing countries. Therefore, the connection between wastewater and human health is linked to access to sanitation and to human waste disposal. Adequate sanitation is expected to create a barrier between disposed human excreta and sources of drinking water. Different approaches to wastewater management are required for different geographical regions and different stages of economic governance depending on the capacity to manage wastewater. Effective wastewater management can contribute to overcome the challenges of water scarcity. Separate collection of human urine at its source is one promising approach that strongly reduces the economic and load demands on wastewater treatment plants (WWTP). Treatment of source-separated urine appears as a sanitation system that is affordable, produces a valuable fertiliser, reduces pollution of water resources and promotes health. However, the technical realisation of urine separation still faces challenges. Biological hydrolysis of urea causes a strong increase of ammonia and pH. Under these conditions ammonia volatilises which can cause odour problems and significant nitrogen losses. The above problems can be avoided by urine stabilisation. Biological nitrification is a suitable process for stabilisation of urine. Urine is a highly concentrated nutrient solution which can lead to strong inhibition effects during bacterial nitrification. This can further lead to process instabilities. The major cause of instability is accumulation of the inhibitory intermediate compound nitrite, which could lead to process breakdown. Enhanced on-line nitrite monitoring can be applied in biological source-separated urine nitrification reactors as a sustainable and efficient way to improve the reactor performance, avoiding reactor failures and eventual loss of biological activity. Spectrophotometry appears as a promising candidate for the development and application of on-line nitrite monitoring. Spectroscopic methods together with chemometrics are presented in this work as a powerful tool for estimation of nitrite concentrations. Principal component regression (PCR) is applied for the estimation of nitrite concentrations using an immersible UV sensor and off-line spectra acquisition. The effect of particles and the effect of saturation, respectively, on the UV absorbance spectra are investigated. The analysis allows to conclude that (i) saturation has a substantial effect on nitrite estimation; (ii) particles appear to have less impact on nitrite estimation. In addition, improper mixing together with instabilities in the urine nitrification process appears to significantly reduce the performance of the estimation model.
Resumo:
Field Lab in Entrepreneurial Innovative Ventures
Resumo:
Following the European Commission’s 2009 Recommendation on the Regulatory Treatment of Fixed and Mobile Termination Rates in the EU, the Portuguese regulatory authority (ANACOM) decided to reduce termination prices in mobile networks to their long-run incremental cost (LRIC). Nevertheless, no serious quantitative assessment of the potential effects of this decision was carried out. In this paper, we adapt and calibrate the Harbord and Hoernig (2014) model of the UK mobile telephony market to the Portuguese reality, and simulate the likely impact on consumer surplus, profits and welfare of four different regulatory approaches: pure LRIC, reciprocal termination charges with fixed networks, “bill & keep”, and asymmetric termination rates. Our results show that reducing MTRs does increase social welfare, profits and consumer surplus in the fixed market, but mobile subscribers are seriously harmed by this decision.
Resumo:
RESUMO: A hipertensão arterial (HA) é uma patologia altamente prevalente, embora claramente subdiagnosticada, em doentes com síndrome de apneia obstrutiva do sono (SAOS). Estas duas patologias apresentam uma estreita relação e a monitorização ambulatória da pressão arterial (MAPA), por um período de 24 horas, parece ser o método mais preciso para o diagnóstico de hipertensão em doentes com SAOS. No entanto, esta ferramenta de diagnóstico para além de ser dispendiosa e envolver um número acrescido de meios técnicos e humanos, é mais morosa e, por conseguinte, não é utilizada por rotina no contexto do diagnóstico da SAOS. Por outro lado, apesar da aplicação de pressão positiva contínua nas vias aéreas (CPAP – Continous Positive Airway Pressure) ser considerada a terapêutica de eleição para os doentes com SAOS, o seu efeito no abaixamento da pressão arterial (PA) parece ser modesto, exigindo, por conseguinte, a implementação concomitante de terapêutica anti-hipertensora. Acontece que são escassos os dados relativos aos regimes de fármacos anti-hipertensores utilizados em doentes com SAOS e, acresce ainda que, as guidelines terapêuticas para o tratamento farmacológico da HA, neste grupo particular de doentes, permanecem, até ao momento, inexistentes. A utilização de modelos animais de hipóxia crónica intermitente (CIH), que mimetizam a HA observada em doentes com SAOS, revela-se extremamente importante, uma vez que se torna imperativo identificar fármacos que promovam um controle adequado da PA neste grupo de doentes. No entanto, estudos concebidos com o intuito de investigar o efeito anti-hipertensor dos fármacos neste modelo animal revelam-se insuficientes e, por outro lado, os escassos estudos que testaram fármacos anti-hipertensores neste modelo não foram desenhados para responder a questões de natureza farmacológica. Acresce ainda que se torna imprescindível garantir a escolha de um método para administração destes fármacos que seja não invasivo e que minimize o stress do animal. Embora a gavagem seja uma técnica indiscutivelmente eficaz e amplamente utilizada para a administração diária de fármacos a animais de laboratório, ela compreende uma sequência de procedimentos geradores de stress para os animais e, que podem por conseguinte, constituir um viés na interpretação dos resultados obtidos. O objectivo global da presente investigação translacional foi contribuir para a identificação de fármacos anti-hipertensores mais efectivos para o tratamento da HT nos indivíduos com SAOS e investigar mecanismos subjacentes aos efeitos sistémicos associadas à SAOS bem como a sua modulação por fármacos anti-hipertensores. Os objectivos específicos foram: em primeiro lugar,encontrar novos critérios, baseados nas medidas antropométricas, que permitam a identificação de doentes com suspeita de SAOS, que erroneamente se auto-classifiquem como nãohipertensos, e desta forma promover um uso mais criterioso do MAPA; em segundo lugar, investigar a existência de uma hipotética associação entre os esquemas de fármacos antihipertensores e o controle da PA (antes e após a adaptação de CPAP) em doentes com SAOS em terceiro lugar, avaliar a eficácia do carvedilol (CVD), um fármaco bloqueador β-adrenérgico não selectivo com actividade antagonista α1 intrínseca e propriedades anti-oxidantes num modelo animal de hipertensão induzida pela CIH; em quarto lugar, explorar os efeitos da CIH sobre o perfil farmacocinético do CVD; e, em quinto lugar, investigar um método alternativo à gavagem para a administração crónica de fármacos anti-hipertensores a animais de laboratório. Com este intuito, na primeira fase deste projecto, fizemos uso de uma amostra com um número apreciável de doentes com SAOS (n=369), que acorreram, pela primeira vez, à consulta de Patologia do Sono do CHLN e que foram submetidos a um estudo polissonográfico do sono, à MAPA e que preencheram um questionário que contemplava a obtenção de informação relativa ao perfil da medicação anti-hipertensora em curso. Numa segunda fase, utilizámos um modelo experimental de HT no rato induzida por um paradigma de CIH. Do nosso trabalho resultaram os seguintes resultados principais: em primeiro lugar, o índice de massa corporal (IMC) e o perímetro do pescoço (PP) foram identificados como preditores independentes de “auto-classificação errónea” da HA em doentes com suspeita de SAOS; em segundo lugar, não encontramos qualquer associação com significado estatístico entre os vários esquemas de fármacos anti-hipertensores bem como o número de fármacos incluídos nesse esquemas, e o controle da PA (antes e depois da adaptação do CPAP); em terceiro lugar, apesar das doses de 10, 30 e 50 mg/kg de carvedilol terem promovido uma redução significativa da frequência cardíaca, não foi observado qualquer decréscimo na PA no nosso modelo animal; em quarto lugar, as razões S/(R+S) dos enantiómeros do CVD nos animais expostos à CIH e a condições de normóxia revelaram-se diferentes; e, em quinto lugar, a administração oral voluntária mostrou ser um método eficaz para a administração diária controlada de fármacos anti-hipertensores e que é independente da manipulação e contenção do animal. Em conclusão, os resultados obtidos através do estudo clínico revelaram que o controle da PA, antes e após a adaptação do CPAP, em doentes com SAOS é independente, quer do esquema de fármacos anti-hipertensores, quer do número de fármacos incluídos num determinado esquema. Os nossos resultados salientam ainda a falta de validade da chamada self-reported hypertension e sugerem que em todos os doentes com suspeita de SAOS, com HA não diagnosticada e com um IMC e um PP acima de 27 kg/m2 e 39 cm, respectivamente, a confirmação do diagnóstico de HA deverá ser realizada através da MAPA, ao invés de outros métodos que com maior frequência são utilizados com este propósito. Os resultados obtidos no modelo animal de HA induzida pela CIH sugerem que o bloqueio do sistema nervoso simpático, juntamente com os supostos efeitos pleiotrópicos do CVD, não parece ser a estratégia mais adequada para reverter este tipo particular de hipertensão e indicam que as alterações farmacocinéticas induzidas pela CIH no ratio S/(R+S) não justificam a falta de eficácia anti-hipertensora do CVD observada neste modelo animal. Por último, os resultados do presente trabalho suportam ainda a viabilidade da utilização da administração oral voluntária, em alternativa à gavagem, para a administração crónica de uma dose fixa de fármacos anti-hipertensores.---------------------------- ABSTRACT: Hypertension (HT) is a highly prevalent condition, although under diagnosed, in patients with obstructive sleep apnea (OSA). These conditions are closely related and 24-hour ambulatory blood pressure monitoring (ABPM) seems to be the most accurate measurement for diagnosing hypertension in OSA. However, this diagnostic tool is expensive and time-consuming and, therefore, not routinely used. On the other hand, although continuous positive airway pressure (CPAP) is considered the gold standard treatment for symptomatic OSA, its lowering effect on blood pressure (BP) seems to be modest and, therefore, concomitant antihypertensive therapy is still required. Data on antihypertensive drug regimens in patients with OSA are scarce and specific therapeutic guidelines for the pharmacological treatment of hypertension in these patients remain absent. The use of animal models of CIH, which mimic the HT observed in patients with OSA, is extremely important since it is imperative to identify preferred compounds for an adequate BP control in this group of patients. However, studies aimed at investigating the antihypertensive effect of antihypertensive drugs in this animal model are insufficient, and most reports on CIH animal models in which drugs have been tested were not designed to respond to pharmacological issues. Moreover, when testing antihypertensive drugs (AHDs) it becomes crucial to ensure the selection of a non-invasive and stress-free method for drug delivery. Although gavage is effective and a widely performed technique for daily dosing in laboratory rodents, it comprises a sequence of potentially stressful procedures for laboratory animals that may constitute bias for the experimental results. The overall goal of the present translational research was to contribute to identify more effective AHDs for the treatment of hypertension in patients with OSA and investigate underlying mechanisms of systemic effects associated with OSA, as well as its modulation by AHDs. The specific aims were: first, to find new predictors based on anthropometric measures to identify patients that misclassify themselves as non-hypertensive, and thereby promote the selective use of ABPM; second, to investigate a hypothetical association between ongoing antihypertensive regimens and BP control rates in patients with OSA, before and after CPAP adaptation; third, to determine, in a rat model of CIH-induced hypertension, the efficacy of carvedilol (CVD), a nonselective beta-blocker with intrinsic anti-α1-adrenergic activity and antioxidant properties; fourth, to explore the effects of CIH on the pharmacokinetics profile of CVD and fifth, to investigate an alternative method to gavage, for chronic administration of AHDs to laboratory rats. For that, in the first phase of this project, we used a sizeable sample of patients with OSA (n=369), that attended a first visit at Centro Hospitalar Lisboa Norte, EPE Sleep Unit, and underwent overnight polysomnography, 24-h ABPM and filled a questionnaire that included ongoing antihypertensive medication profile registration. In the second phase, a rat experimental model of HT induced by a paradigm of CIH that simulates OSA was used. The main findings of this work were: first, body mass index (BMI) and neck circumference (NC) were identified as independent predictors of hypertension misclassification in patients suspected of OSA; second, in patients with OSA, BP control is independent of both the antihypertensive regimen and the number of antihypertensive drugs, either before or after CPAP adaptation; third, although the doses of 10, 30 and 50 mg/Kg of CVD promoted a significant reduction in heart rate, no decrease in mean arterial pressure was observed; fourth, the S/(R+S) ratios of CVD enantiomers, between rats exposed to CIH and normoxic conditions, were different and fifth, voluntary ingestion proved to be an effective method for a controlled daily dose administration, with a define timetable, that is independent of handling and restraint procedures. In conclusion, the clinical study showed that BP control in OSA patients is independent of both the antihypertensive regimen and the number of antihypertensive drugs. Additionally, our results highlight the lack of validity of self-reported hypertension and suggest that all patients suspected of OSA with undiagnosed hypertension and with a BMI and NC above 27 Kg/m2 and 39 cm should be screened for hypertension, through ABPM. The results attained in the rat model of HT related to CIH suggest that the blockade of the sympathetic nervous system together with the putative pleiotropic effects of carvedilol is not able to revert hypertension induced by CIH and point out that the pharmacokinetic changes induced by CIH on S/(R+S) ratio are not apparently responsible for the lack of efficacy of carvedilol in reversing this particular type of hypertension. Finally, the results here presented support the use of voluntary oral administration as a viable alternative to gavage for chronic administration of a fixed dose of AHDs.
Resumo:
According to a recent Eurobarometer survey (2014), 68% of Europeans tend not to trust national governments. As the increasing alienation of citizens from politics endangers democracy and welfare, governments, practitioners and researchers look for innovative means to engage citizens in policy matters. One of the measures intended to overcome the so-called democratic deficit is the promotion of civic participation. Digital media proliferation offers a set of novel characteristics related to interactivity, ubiquitous connectivity, social networking and inclusiveness that enable new forms of societal-wide collaboration with a potential impact on leveraging participative democracy. Following this trend, e-Participation is an emerging research area that consists in the use of Information and Communication Technologies to mediate and transform the relations among citizens and governments towards increasing citizens’ participation in public decision-making. However, despite the widespread efforts to implement e-Participation through research programs, new technologies and projects, exhaustive studies on the achieved outcomes reveal that it has not yet been successfully incorporated in institutional politics. Given the problems underlying e-Participation implementation, the present research suggested that, rather than project-oriented efforts, the cornerstone for successfully implementing e-Participation in public institutions as a sustainable added-value activity is a systematic organisational planning, embodying the principles of open-governance and open-engagement. It further suggested that BPM, as a management discipline, can act as a catalyst to enable the desired transformations towards value creation throughout the policy-making cycle, including political, organisational and, ultimately, citizen value. Following these findings, the primary objective of this research was to provide an instrumental model to foster e-Participation sustainability across Government and Public Administration towards a participatory, inclusive, collaborative and deliberative democracy. The developed artefact, consisting in an e-Participation Organisational Semantic Model (ePOSM) underpinned by a BPM-steered approach, introduces this vision. This approach to e-Participation was modelled through a semi-formal lightweight ontology stack structured in four sub-ontologies, namely e-Participation Strategy, Organisational Units, Functions and Roles. The ePOSM facilitates e-Participation sustainability by: (1) Promoting a common and cross-functional understanding of the concepts underlying e-Participation implementation and of their articulation that bridges the gap between technical and non-technical users; (2) Providing an organisational model which allows a centralised and consistent roll-out of strategy-driven e-Participation initiatives, supported by operational units dedicated to the execution of transformation projects and participatory processes; (3) Providing a standardised organisational structure, goals, functions and roles related to e-Participation processes that enhances process-level interoperability among government agencies; (4) Providing a representation usable in software development for business processes’ automation, which allows advanced querying using a reasoner or inference engine to retrieve concrete and specific information about the e-Participation processes in place. An evaluation of the achieved outcomes, as well a comparative analysis with existent models, suggested that this innovative approach tackling the organisational planning dimension can constitute a stepping stone to harness e-Participation value.
Resumo:
ABSTRACT: Background: Childhood is a critical time for social and emotional development, educational progress and mental health prevention. Mental health for children and adolescents is defined by the achievement of expected developmental, cognitive, social and emotional skills. The development of child-adolescent mental health services (CAMHS) is a necessity for each country, not only as a prevention measure for the wellbeing of people, but also as an investment to the future of countries. Qualitative evaluation of services is the only way to ensure whether services function under quality standards and increase the possibility of better outcomes for their patients. This study examines the greek outpatient CAMHS against the British Standards of National Institute of Excellence for community CAMHS. The Standards assessed refer to the areas of Assessment, Care and Intervention. Objectives: The main objectives of the study are 1) to evaluate Greek outpatient CAMHS in the Attica region 2) to promote the evaluation process for mental health services in Greece. Methods: Due to the fact that Greek services are based on the British model, the tool used was the British self-review questionnaire of Quality Network for Community CAMHS(QNCC).The tool was translated, adapted and posted to services. Twelve out of twenty outpatient CAMHS of Attica (including Athens) responded. Data was collected and performed by the Statistical Package for Social Sciences SPSS. Results: The study resulted that the CAMHS examined, meet moderately the British Standards of 1) Referral and Access, 2) Assessment & Care planning, 3) Care & Intervention. Two out of twelve services examined, meet the standards of "Assessment and Care" in a higher percentage between 75% and 100%. Conclusions: The paper describes a satisfactory function of CAMHS in Attica prefecture taking into consideration the extremely difficult political situation of Greece at the time of the research. Strong and weak domains are identified. Also the translation and adaptation of British tools promote the evaluation process and quality assurance of Greek CAMHS.
Resumo:
The advent of bioconjugation impacted deeply the world of sciences and technology. New biomolecules were found, biological processes were understood, and novel methodologies were formed due to the fast expansion of this area. The possibility of creating new effective therapies for diseases like cancer is one of big applications of this now big area of study. Off target toxicity was always the problem of potent small molecules with high activity towards specific tumour targets. However, chemotherapy is now selective due to powerful linkers that connect targeting molecules with affinity to interesting biological receptors and cytotoxic drugs. This linkers must have very specific properties, such as high stability in plasma, no toxicity, no interference with ligand affinity nor drug potency, and at the same time, be able to lyse once inside the target molecule to release the therapeutic warhead. Bipolar environments between tumour intracellular and extracellular medias are usually exploited by this linkers in order to complete this goal. The work done in this thesis explores a new model for that same task, specific cancer drug delivery. Iminoboronates were studied due to its remarkable selective stability towards a wide pH range and endogenous molecules. A fluorescence probe was design to validate this model by creating an Off/On system and determine the payload release location in situ. A process was optimized to synthetize the probe 8-(1-aminoethyl)-7-hydroxy-coumarin (1) through a reductive amination reaction in a microwave reactor with 61 % yield. A method to conjugate this probe to ABBA was also optimized, obtaining the iminoboronate in good yields in mild conditions. The iminoboronate model was studied regarding its stability in several simulated biological environments and each half-life time was determined, showing the conjugate is stable most of the cases except in tumour intracellular systems. The construction of folate-ABBA-coumarin bioconjugate have been made to complete this evaluation. The ability to be uptaken by a cancer cell through endocytosis process and the conjugation delivery of coumarin fluorescence payload are two features to hope for in this construct.