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Ensuring Access to Safe and Nutritious Food for All Through the Transformation of Food Systems
Anuário científico da Escola Superior de Tecnologia da Saúde de Lisboa - 2021
É com grande prazer que apresentamos a mais recente edição (a 11.ª) do Anuário Científico da Escola Superior de Tecnologia da Saúde de Lisboa. Como instituição de ensino superior, temos o compromisso de promover e incentivar a pesquisa científica em todas as áreas do conhecimento que contemplam a nossa missão. Esta publicação tem como objetivo divulgar toda a produção científica desenvolvida pelos Professores, Investigadores, Estudantes e Pessoal não Docente da ESTeSL durante 2021. Este Anuário é, assim, o reflexo do trabalho árduo e dedicado da nossa comunidade, que se empenhou na produção de conteúdo científico de elevada qualidade e partilhada com a Sociedade na forma de livros, capítulos de livros, artigos publicados em revistas nacionais e internacionais, resumos de comunicações orais e pósteres, bem como resultado dos trabalhos de 1º e 2º ciclo. Com isto, o conteúdo desta publicação abrange uma ampla variedade de tópicos, desde temas mais fundamentais até estudos de aplicação prática em contextos específicos de Saúde, refletindo desta forma a pluralidade e diversidade de áreas que definem, e tornam única, a ESTeSL. Acreditamos que a investigação e pesquisa científica é um eixo fundamental para o desenvolvimento da sociedade e é por isso que incentivamos os nossos estudantes a envolverem-se em atividades de pesquisa e prática baseada na evidência desde o início dos seus estudos na ESTeSL. Esta publicação é um exemplo do sucesso desses esforços, sendo a maior de sempre, o que faz com que estejamos muito orgulhosos em partilhar os resultados e descobertas dos nossos investigadores com a comunidade científica e o público em geral. Esperamos que este Anuário inspire e motive outros estudantes, profissionais de saúde, professores e outros colaboradores a continuarem a explorar novas ideias e contribuir para o avanço da ciência e da tecnologia no corpo de conhecimento próprio das áreas que compõe a ESTeSL. Agradecemos a todos os envolvidos na produção deste anuário e desejamos uma leitura inspiradora e agradável.info:eu-repo/semantics/publishedVersio
PreFair: Privately Generating Justifiably Fair Synthetic Data
When a database is protected by Differential Privacy (DP), its usability is
limited in scope. In this scenario, generating a synthetic version of the data
that mimics the properties of the private data allows users to perform any
operation on the synthetic data, while maintaining the privacy of the original
data. Therefore, multiple works have been devoted to devising systems for DP
synthetic data generation. However, such systems may preserve or even magnify
properties of the data that make it unfair, endering the synthetic data unfit
for use. In this work, we present PreFair, a system that allows for DP fair
synthetic data generation. PreFair extends the state-of-the-art DP data
generation mechanisms by incorporating a causal fairness criterion that ensures
fair synthetic data. We adapt the notion of justifiable fairness to fit the
synthetic data generation scenario. We further study the problem of generating
DP fair synthetic data, showing its intractability and designing algorithms
that are optimal under certain assumptions. We also provide an extensive
experimental evaluation, showing that PreFair generates synthetic data that is
significantly fairer than the data generated by leading DP data generation
mechanisms, while remaining faithful to the private data.Comment: 15 pages, 11 figure
On p-group isomorphism: Search-to-decision, counting-to-decision, and nilpotency class reductions via tensors
In this paper we study some classical complexity-theoretic questions regarding Group Isomorphism (GpI). We focus on p-groups (groups of prime power order) with odd p, which are believed to be a bottleneck case for GpI, and work in the model of matrix groups over finite fields. Our main results are as follows. Although search-to-decision and counting-to-decision reductions have been known for over four decades for Graph Isomorphism (GI), they had remained open for GpI, explicitly asked by Arvind & Torán (Bull. EATCS, 2005). Extending methods from Tensor Isomorphism (Grochow & Qiao, ITCS 2021), we show moderately exponential-time such reductions within p-groups of class 2 and exponent p. Despite the widely held belief that p-groups of class 2 and exponent p are the hardest cases of GpI, there was no reduction to these groups from any larger class of groups. Again using methods from Tensor Isomorphism (ibid.), we show the first such reduction, namely from isomorphism testing of p-groups of “small” class and exponent p to those of class two and exponent p. For the first results, our main innovation is to develop linear-algebraic analogues of classical graph coloring gadgets, a key technique in studying the structural complexity of GI. Unlike the graph coloring gadgets, which support restricting to various subgroups of the symmetric group, the problems we study require restricting to various subgroups of the general linear group, which entails significantly different and more complicated gadgets. The analysis of one of our gadgets relies on a classical result from group theory regarding random generation of classical groups (Kantor & Lubotzky, Geom. Dedicata, 1990). For the nilpotency class reduction, we combine a runtime analysis of the Lazard Correspondence with Tensor Isomorphism-completeness results (Grochow & Qiao, ibid.)
A suite of quantum algorithms for the shortestvector problem
Crytography has come to be an essential part of the cybersecurity infrastructure that provides a safe environment for communications in an increasingly connected world. The advent of quantum computing poses a threat to the foundations of the current widely-used cryptographic model, due to the breaking of most of the cryptographic algorithms used to provide confidentiality, authenticity, and more. Consequently a new set of cryptographic protocols have been designed to be secure against quantum computers, and are collectively known as post-quantum cryptography (PQC). A forerunner among PQC is lattice-based cryptography, whose security relies upon the hardness of a number of closely related mathematical problems, one of which is known as the shortest vector problem (SVP).
In this thesis I describe a suite of quantum algorithms that utilize the energy minimization principle to attack the shortest vector problem. The algorithms outlined span the gate-model and continuous time quantum computing, and explore methods of parameter optimization via variational methods, which are thought to be effective on near-term quantum computers. The performance of the algorithms are analyzed numerically, analytically, and on quantum hardware where possible. I explain how the results obtained in the pursuit of solving SVP apply more broadly to quantum algorithms seeking to solve general real-world problems; minimize the effect of noise on imperfect hardware; and improve efficiency of parameter optimization.Open Acces
Photography and Aesthetics: a critical study on visual and textual narratives in the lifework of Sergio Larraín and its impact in 20th century Europe and Latin America
The main focus of this study is a theoretical exploration of critical approaches applicable to the work of the Chilean photographer Sergio Larraín (1931-2012). It presents analytical tools to contextualise and understand the importance and impact of his work in photographic studies and his portrayal of twentieth-century Latin American and European culture. It inspects in depth a large portion of his photo work, which is still only partially published and mostly reduced to his "active" period as a photojournalist, aside from the personal photographic exploration of his early and late career (C. Mena). This extended material creates a broader scope for understanding his photographs and him as a canonical photographer. This study analyses the photographer's trajectory as discourses of recollection of historical memory in time (Mauad) to trace Larraín's collective memory associated with his visual production. Such analysis helps decode his visual imagery and his projection and impact on the European and Latin American culture. This strategy helps solve a two fold problem: firstly, it generates an interpretive consistency to understand the Chilean's photographic practice; secondly, it explores the power of images as an aesthetic experience in the installation of nationalist ideologies and the creation of imaginaries (B. Anderson 163)
Towards the development of care management in community care for elderly people in Korea
This study is concerned with the feasibility of several forms of care management in the development of community care for elderly people in Korea. Chapter one introduces the background of community care in Korea in the light of demographic, socio-economic, and political realities. This chapter reviews the changing Korean society as a barometer to understand the scope, size, and speed of social needs, especially community care for elderly people, over the last few decades. Chapter two explores various definitions, concepts, and theories of community, community care, and care management by building upon trends previously established in the research. This helps to identify the different models of care management and the pre-conditions necessary for the application of different models in Korea. Chapter three explores what factors have affected the development of community care, and what community dare has achieved for elderly people in the UK. Especially, care management in community care for elderly people in the UK is examined in detail. Chapter four details the findings of field research on community care for elderly people in Korea. This covers the needs of elderly people and their carers, and the social worker's tasks and available resources. The potential for the use of care management based on the findings of field research is assessed. Chapter five investigates whether the UK models of care management are suitable for Korean society, which interventions are useful for developing care management, and the strategies, and principles involved
Anytime algorithms for ROBDD symmetry detection and approximation
Reduced Ordered Binary Decision Diagrams (ROBDDs) provide a dense and memory efficient representation of Boolean functions. When ROBDDs are applied in logic synthesis, the problem arises of detecting both classical and generalised symmetries. State-of-the-art in symmetry detection is represented by Mishchenko's algorithm. Mishchenko showed how to detect symmetries in ROBDDs without the need for checking equivalence of all co-factor pairs. This work resulted in a practical algorithm for detecting all classical symmetries in an ROBDD in O(|G|³) set operations where |G| is the number of nodes in the ROBDD. Mishchenko and his colleagues subsequently extended the algorithm to find generalised symmetries. The extended algorithm retains the same asymptotic complexity for each type of generalised symmetry. Both the classical and generalised symmetry detection algorithms are monolithic in the sense that they only return a meaningful answer when they are left to run to completion. In this thesis we present efficient anytime algorithms for detecting both classical and generalised symmetries, that output pairs of symmetric variables until a prescribed time bound is exceeded. These anytime algorithms are complete in that given sufficient time they are guaranteed to find all symmetric pairs. Theoretically these algorithms reside in O(n³+n|G|+|G|³) and O(n³+n²|G|+|G|³) respectively, where n is the number of variables, so that in practice the advantage of anytime generality is not gained at the expense of efficiency. In fact, the anytime approach requires only very modest data structure support and offers unique opportunities for optimisation so the resulting algorithms are very efficient. The thesis continues by considering another class of anytime algorithms for ROBDDs that is motivated by the dearth of work on approximating ROBDDs. The need for approximation arises because many ROBDD operations result in an ROBDD whose size is quadratic in the size of the inputs. Furthermore, if ROBDDs are used in abstract interpretation, the running time of the analysis is related not only to the complexity of the individual ROBDD operations but also the number of operations applied. The number of operations is, in turn, constrained by the number of times a Boolean function can be weakened before stability is achieved. This thesis proposes a widening that can be used to both constrain the size of an ROBDD and also ensure that the number of times that it is weakened is bounded by some given constant. The widening can be used to either systematically approximate an ROBDD from above (i.e. derive a weaker function) or below (i.e. infer a stronger function). The thesis also considers how randomised techniques may be deployed to improve the speed of computing an approximation by avoiding potentially expensive ROBDD manipulation
Wildlife wars in an age of changing climate and social change: Assessing the social and ecological dimensions of Human Wildlife Conflict and Conservation Initiatives in the Rangelands of Kenya
Human wildlife conflict is an on-going global problem that is threatening the existence of iconic species of wildlife like Elephants and the big cats. It is also a human rights issue as it threatens the livelihoods of the many people who in most cases have been structurally marginalized and vulnerable. It is not wise to think that human wildlife conflict will disappear by itself. A lot of work has gone into trying to understand the problem and how to solve it. However, most of the efforts target local area challenges with short-term solutions that are not based on an understanding of landscape level processes and global issues like climate change. Driven by our long-term experience of working community based natural resources management and knowledge of the global issues, we sought to understand the human dimension of human-wildlife dynamics and particularly the conflict affecting pastoralists that is occasioned by predation of their livestock by lions and other big cats.
We used mixed methods to examine theoretical assumptions that have been put forward on human wildlife conflict and link human wildlife conflict (predation events) to climate change dynamics. Using focus group discussions, we collected both qualitative and quantitative data, which we analysed qualitatively and statistically. The quantitative findings were validated and explained better by use of qualitative data collected from three communities living in the larger southern Kenya rangelands landscape. The aim of this thesis was to (1) Establish the link between human wildlife conflicts and climate (rainfall) over seasons within a year and annual time scales. (2) Establish what motivates the pastoralists to kill lions (3) Assess how perceptions of people living with the big cats change over time and (4) Review the role of communities and multi-level governance biodiversity conservation.
The findings from this research show that community members value the ecosystem services and goods they receive from nature. While the challenges associated with climate change (drought) are likely to increase the prevalence of human wildlife conflict, the pastoralists are more tolerant to the wildlife when there is proper compensation or consolation. The results also show that the Maasai only kill lions when they are certain the lion is the culprit animal that caused the loss of their livestock, not indiscriminately. Our comparison of the results over a period of ten years show that the community members' attitudes, behaviour, and perceptions of wildlife changed over time and across regions as a result of a change in the climate factors and the attitude of the conservation authorities. Compensation programs and other forms of incentives to the pastoralists or local people for living with wildlife would go a long way in ensuring tolerance and co-existence with wildlife. With co-existence, any negative interactions between people and wildlife is overshadowed by the benefits and therefore less and less of human wildlife conflict. Our results also show that governance of natural resources and local institutions, rules and norms on wildlife and natural resources conservation are important pillars in mitigating human wildlife conflict. This research also shows that while people are affected as individuals, actions to minimize the challenges are better decided on and actioned at a community level. Community conservancies with a functional governance system may be the basis for sustainable rangelands, wildlife, and livelihoods. Actions at a wider landscape are likely to have better results than local level, short-term, and poorly resourced interventions
Safe Water for All: A Multi-Modal Approach to North Alabama\u27s Water Resources
Environmental degradation is a destructive force produced by the human disturbance of pollution. It is a phenomenon that gradually evolves landscapes over time resulting in irreversible outcomes. Environmental degradation physically affects spaces’ resources, objects, and inhabiting humans. This study observes the impacts of pollution beyond physical boundaries and how it affects human identity/sense of place through the utilization of geographic information systems. Specifically, it examines cultural identity developed through human experiences and connections to landscapes containing water resources. Following, pollution contaminates water resources disrupting experiences and connections thus causing the cultural identity to disappear. The case study applied to this research is the Alabama cultural identity connected to the Tennessee River that flows through the northern portion of North Alabama.
Alabama citizens formulate deep connections to landscapes through farming, attaching religious symbolism to the environment through biblical references, and perform Christian practices with objects found in spaces (Tuan, 1974). Due to the contamination in the Tennessee River, this affects utilization of water for farming and Christian practices performed in the river because of the threat pollution poses. As a result, Alabama cultural identity disappears halt of experiences against an unfamiliar landscape degraded by pollution. Testing this hypothesis, this research utilizes a mixed methods approach applying multiple analyses and models.
Participatory observations, surveys, and interviews accomplished the qualitative analysis of Alabama culture. Then, the collection of multiple amounts hydrological data, survey statistics, interviews, poverty data and land use data were inputted into the geographically weighted regression model completing the quantitative analysis of water pollution. The model that was implemented was the Arc Story Map. Then, Arc Story Map presented the data visually for the public
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