An investigation of functional MRI activation reproducibility

Imperial Users onl

From the Information Bottleneck to the Privacy Funnel

We focus on the privacy-utility trade-off encountered by users who wish to disclose some information to an analyst, that is correlated with their private data, in the hope of receiving some utility. We rely on a general privacy statistical inference framework, under which data is transformed before it is disclosed, according to a probabilistic privacy mapping. We show that when the log-loss is introduced in this framework in both the privacy metric and the distortion metric, the privacy leakage and the utility constraint can be reduced to the mutual information between private data and disclosed data, and between non-private data and disclosed data respectively. We justify the relevance and generality of the privacy metric under the log-loss by proving that the inference threat under any bounded cost function can be upper-bounded by an explicit function of the mutual information between private data and disclosed data. We then show that the privacy-utility tradeoff under the log-loss can be cast as the non-convex Privacy Funnel optimization, and we leverage its connection to the Information Bottleneck, to provide a greedy algorithm that is locally optimal. We evaluate its performance on the US census dataset

Pour une étude globale de l’iconographie des omeyyades de Syrie et d’Espagne (VIII-XIe): le cas des calendriers et des thèmes agricoles

Pour une étude globale de l’iconographie des omeyyades de Syrie et d’Espagne (VIII-XIe): le cas des calendriers et des thèmes agricolesPour une étude globale de l’iconographie desomeyyades de Syrie et d’Espagne (VIII-XIe):le cas des calendriers et des thèmes agricole

Isolation and Characterisation of Halogenated and Bioactive Compounds from Thalassospira sp. and Alteromonas sp.

Bacterial natural products have contributed with a large part of the bioactive compounds that lead to drugs, and the biggest portion of the marketed antibiotics are bacterial products or their derivatives. Marine bacteria are not yet investigated to the same extend as their terrestrial counterparts. Therefore, they are considered a promising source for novel bioactive metabolites for drug development, which has been a trigger for the work carried out in this thesis. In this thesis, three Arctic marine bacteria of the genus Thalassospira, Alteromonas and Pseudomonas were investigated. The bacterial strains were cultivated, extracted and pre-fractionated. The fractions were screened for antibacterial and anticancer activity, and active fractions were re-fractionated. The bioactive re-fractionated extracts were dereplicated to investigate if the compounds suspected of being active, were novel or had been previously reported. Compounds assumed to be bioactive, as well as those with interesting chemical properties were isolated and characterised. One bioactive compound was isolated from the bacterial strain Thalassospira sp. The compound was active in both antibacterial and anticancer assays, and its structure remains to be elucidated. A di-halogenated compound was also isolated from this strain, it was however found to be chemically unstable. Moreover, three compounds were isolated from the bacterial strain Alteromonas sp. that remain to be structure elucidated and screened for bioactivity

An unfamiliar face, an unfamiliar environment: Investigating educators’ understanding of their attachment relationships with infants and toddlers in Early Childhood Education and Care settings

Attachment theory has influenced research, policy and practice over the last six decades, offering a framework for understanding risk and protective factors in early childhood. However, this work has primarily been influenced from a medical health or psychological perspective. Despite the literature highlighting the importance of attachment relationships, there is limited research relating to educators’ knowledge and understanding of attachment theory. The first years of life are considered a sensitive period for attachment development, and with families increasingly utilising formal care for their infants and toddlers, educators are in a prime position to use attachment theory to inform their practices within education and care (ECEC) settings. The aims of this study were to investigate educators’ knowledge and understanding of attachment theory and the practices they use to support the development of secure infant/toddler–caregiver relationships. Drawing upon an interpretive theoretical framework, this study focused on understanding attachment theory and practice from multiple perspectives through the voices of early childhood educators. Using multiple methodologies such as a mixed method design enhances an interpretive framework. Data was collected via an online survey through a closed Facebook page as well as personal contacts of the researcher, email and snowballing. From this survey, 488 Australian educators responded demonstrating a wide interest in the topic of attachment. One early childhood service was selected to participate in semi-structured interviews. Observations of their attachment practices were documented using the Reflect, Respect, Relate tool. Quantitative data was analysed using Qualtrics software with Nvivo used for qualitative data to code key concepts and emerging themes. A national survey provided a general picture of educator perceptions and practices whilst the observations and interviews supported a deeper exploration into themes emerging from the survey. Findings highlighted educators’ desire to access further support to understand how to interpret the Early Years Learning Framework (EYLF) and associated documents in relation to attachment theory. The EYLF proposes that children feel “safe, secure and supported” when they develop attachment relationships with educators (Department of Education, Employment and Workplace Relations [DEEWR], 2009, p. 21). However, little guidance is provided within the framework or accompanying resources about how educators should approach this relationship development. Educators who participated in the study drew upon multiple approaches to support the development of attachment relationships. Their approach varied according to knowledge, understanding and personal experiences of participating in attachment relationships. Additionally, findings indicated that educators require support and access to sufficient knowledge and ongoing professional development relating to attachment theory that is specifically targeted toward ECEC settings. This study is unique in that it investigated the challenges of attachment theory from an educator’s perspective rather than a psychological lens. This research hopes to build upon the existing knowledge of educators and highlight the importance of attachment theory to inform strategic direction and policy development

The effect of additives metal on the D.C conductivity of epoxy resin

The present studies are focused on the modification of the properties of epoxy resin with different additives namely aluminum, copper by preparing of composites systems with percentage (20%, 40% and 50%) of the above additives. The experimental results show that the D.C of conductivity on wt% filler content at ( 293-413 ) K electrical conductivity of all above composites increased with temperature for composites with filler contact and find the excellent electrical conductivity of copper and lie between (2.6*10-10 - 2.1*10-10)?.cm . The activation energy of the electrical conductivity is determined and found to decrease with increasing the filler concentration

Exploring the patients’ and family members’ perspectives on home-based palliative care

Background: Home health care is considered as a partial substitute for institutional long-term care, because patients and families with known poor prognoses prefer to stay home with their loved ones and people mostly cannot bear the cost of care at the hospital. Therefore, the importance of home-based palliative care is raised via a shared and coordinated model for saving lives through care.Purpose: To explore patients\u27 and family members\u27 perspectives and experiences of receiving home-based palliative care services.Method: This was a qualitative exploratory study conducted in Karachi, targeting patients and family members receiving home-based palliative care services. The data collection was done via interviews and simultaneously the interviewer recorded field notes, all carried out within the confines of the participants\u27 own homes. Moreover, the subjects were recruited through purposive sampling, resulting in a total of six patients and six family members. The final number of participants was determined based on data saturation. The inclusion criteria encompassed individuals of all genders, aged 18 and above, and residents of Karachi, Pakistan. Those who were not able to provide information, due to any reason, were excluded from the study. The study adhered strictly to ethical considerations.Findings: The study uncovered several significant themes that provide valuable insights, including caregivers’ availability, patient’s inclusiveness, improved dietary pattern, psychological well-being, and rapid recovery in home-based care. Furthermore, the study identified themes on providing home-based palliative care like family members’ education and keeping back-ups for unforeseen situations. In contrast, the themes identified as home-based care preference over hospital care were: experienced compromised care, hospital anxiety, restricted to the available resources and higher hospital living expenses for patients and family members.Conclusion: The study underscored the importance of adopting a patient-centric approach. It has become evident that the comfort and familiarity of one\u27s home environment provide a conducive backdrop for holistic healing and well-being. Hence, this study provides valuable insights along with limitations like; excluded socioeconomic status, selection and recall biases, and participants’ hesitancy to share information

An information systems security framework for the e-Government Programme of Jordan

Any e-government programme provides e-services as one of the most important means by which the interaction between citizens, businesses and governments takes place. This has brought great opportunities but also raises serious cybersecurity challenges. Critical information assets are facing various potential security risks and threats. Information systems security is necessary to mitigate those risks and threats that are faced by the e-government programme and to safeguard the confidentiality, integrity and availability of the available e-services. In light of the above, the aim of this study is to examine how information security is managed and approached within e-government programmes and the case study of the Ministry of ICT in Jordan informs that aim. The study deconstructs information security through the Technical/Formal/Informal (TFI) framework and enriches that framework by customising it for e-government, expanding it also to include citizens’ online trust. To achieve this aim, a qualitative investigation of the Jordanian e-government programme was conducted by following the research design of a case study in the interpretivist tradition. Furthermore, a survey was used as a complementary phase to examine citizens’ perspectives on e-government security. By combining, analysing and reflecting on the empirical data, a consolidated information security framework was developed for different security aspects, based on the TFI model (technical, formal and informal). The dissertation contributes to the knowledge domain at the intersection of e-government and cybersecurity both practically and theoretically, focusing on technical aspects and non-technical aspects as well. The proposed framework provides an overview of the TFI-categorised elements that can help governments reflect on and manage the security challenges of their corresponding e-government programmes

Developing Learners’ Autonomy-Oriented Physics Teaching Materials to Enhance Students' Science Process Skills

The unavailability of learner autonomy-oriented physics teaching materials which are capable of enhancing students’ science process skills (SPS) of students is becoming a hindrance in one of the public high schools in Banjarmasin, as well as the lack of SPS in students. Thus, this study was carried out with the aim to produce learning materials oriented on learner autonomy orientation to enhance students’ SPS properly. This was based on the validity, practicality, and effectiveness of the developed teaching materials in terms of learning outcomes in the students’ cognitive and psychomotor domains. This research utilized research and development method with the use of the ADDIE development model (Analyze, Design, Develop, Implement, Evaluate). The trial subjects in this study consisted of 34 students of Grade X in one of the public high schools in Banjarmasin. The data were obtained through validation sheets, lesson plan implementation sheets, SPS observation sheets, and learning outcomes tests (LOT). The results indicated that the teaching materials developed were: 1) valid, based on the results of the validator's assessments with the average score of 3.35, categorized in the “valid” category; 2) practical, based on the implementation of lesson plan with the average score of 3.66 in the very good category; 3) effective, seen from the gain score obtained of 0.67 in the “medium” category; 4) SPS achievement of 72.17 in the “good” category. It is then concluded that the learner autonomy-oriented learning materials are feasible to be implemented in classroom activities