Danger theory: the link between AIS and IDS?

We present ideas about creating a next generation Intrusion Detection System (IDS) based on the latest immunological theories. The central challenge with computer security is determining the difference between normal and potentially harmful activity. For half a century, developers have protected their systems by coding rules that identify and block specific events. However, the nature of current and future threats in conjunction with ever larger IT systems urgently requires the development of automated and adaptive defensive tools. A promising solution is emerging in the form of Artificial Immune Systems (AIS): The Human Immune System (HIS) can detect and defend against harmful and previously unseen invaders, so can we not build a similar Intrusion Detection System (IDS) for our computers? Presumably, those systems would then have the same beneficial properties as HIS like error tolerance, adaptation and self-monitoring. Current AIS have been successful on test systems, but the algorithms rely on self-nonself discrimination, as stipulated in classical immunology. However, immunologist are increasingly finding fault with traditional self-nonself thinking and a new ‘Danger Theory’ (DT) is emerging. This new theory suggests that the immune system reacts to threats based on the correlation of various (danger) signals and it provides a method of ‘grounding’ the immune response, i.e. linking it directly to the attacker. Little is currently understood of the precise nature and correlation of these signals and the theory is a topic of hot debate. It is the aim of this research to investigate this correlation and to translate the DT into the realms of computer security, thereby creating AIS that are no longer limited by self-nonself discrimination. It should be noted that we do not intend to defend this controversial theory per se, although as a deliverable this project will add to the body of knowledge in this area. Rather we are interested in its merits for scaling up AIS applications by overcoming self-nonself discrimination problems.

Non-institutionalized nonagenarians health-related quality of life and nutritional status: is there a link between them?

Introduction: Nonagenarian population, clearly increasing, shows different characteristics from the rest of elderly people. Health-related quality of life is a way to study population health in physical, psychological and social dimensions. Objectives: To examine the relationship between nutritional status and health-related quality of life in a group of free-living nonagenarians. Differences with octogenarians were also studied. Methods: Within Villanueva Older Health Study, 20 non-institutionalised people (92.5±3.5 years; 80% women) make the nonagenarian subsample. Nutritional risk was assessed by Mininutritional Assessment questionnaire, dietary intake by a 24-hour dietary recall and health-related quality of life by EuroQoL-5D questionnaire. SPSS was used for statistical analysis. Results: 40% nonagenarians were at risk of malnutrition. Dietary assessment showed magnesium, zinc, potassium, folic acid, vitamin D and vitamin E deficiencies. Problems in mobility were more frequently reported (80%). EQ-5Dindex was associated with MNA (p<0.05). Self-care dimension was associated with calcium and niacin (p<0.05), retinol and cholesterol (p<0.01) intake. Usual activities dimension was associated with niacin (p<0.01) and cholesterol(p<0.05) intake. Pain/discomfort dimension was associated with protein (p<0.01), energy, selenium and niacin (p<0.05) intake. Anxiety/depression was associated with protein(p<0.01) and selenium (p<0.05) intake. Conclusions: Risk of malnutrition is a factor associated to health-related quality of life. Results suggest that energy and some nutrient intakes could be possibly associated to health-related quality of life but further research on this influence is required.

Forming the link between strategic performance and operational success: The development of a balanced scorecard at Lisbon Consulting Group

Directed internship

Using induced pluripotent stem cells to investigate the mechanistic link between Gaucher disease and Parkinson related synucleinopathies

Dissertação de Mestrado, Ciências Biomédicas, Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, 2015

Joint dispersion model with a flexible link

Poster presented at the Workshop on Flexible Models for Longitudinal and Survival Data with Applications in Biostatistics. University of Warwick, Coventry, UK, 27-29 July 2015

Testing the link specification in binary choice models. A semiparametric approach.

Doutoramento em Matemática.

Cytomegalovirus and Langerhans Cell Histiocytosis: Is There a Link?

Background: Langerhans cell histiocytosis is a rare proliferative histiocytic disease of unknown etiology. Histologically, it is characterized by granuloma-like proliferation of Langerhans-type dendritic cells derived from bone marrow. Many investigators have suggested the possible role of viruses such as Epstein-Barr virus, human herpesvirus-6 (HHV-6), herpes simplex virus (HSV) types 1 and 2, and Cytomegalovirus in the pathogenesis of Langerhans cell histiocytosis. Objectives: In this study, we have investigated the presence of Cytomegalovirus in Langerhans cell histiocytosis in Iranian children. Patients and Methods: In this retrospective study, we have investigated the presence of Cytomegalovirus DNA expression, using paraffin-embedded tissue samples of 30 patients with Langerhans cell histiocytosis and 30 age and site-matched controls by qualitative Polymerase Chain Reaction (PCR) method. Results: No significant difference in prevalence of Cytomegalovirus presence between patients and controls was found. Cytomegalovirus was found by qualitative PCR in only 2 (6.66%) out of 30 patients and in 1 (3.3%) of 30 control samples with a P value of 1 (1.00 > 0.05) using chi-square test with OR: 2.07; 95% CI of OR: 0.18 - 24.15. Conclusions: Our findings do not support the hypothesis of a possible role for Cytomegalovirus in the pathogenesis of Langerhans cell histiocytosis.

Grundlagen einer monographie der gattung Fusarium (Link).

"Kleinere mitteilungen."

Mediterranean outflow and its link with upstream conditions in Alboran Sea

The Western Alboran Gyre (WAG) at the eastern entrance of the Strait of Gibraltar can influence the Mediterranean outflow (MOW) by favoring or hampering the flow of Levantine and Western Mediterranean (LIW and WMDW) waters, the main constituents of the MOW. Observations collected at Camarinal sill in the Strait and AVISO data are used to investigate this issue.

Active power control in an islanded microgrid using DC link voltage status

This paper proposes a power balancing strategy for dispatchable and non-dispatchable sources in an islanded microgrid. This control method enables energy storage system that employs a voltage-band at a dc busbar to maintain grid voltage stability for short period disturbances in a network. This voltage-band, applied to obtain maximum benefit from the storage system, depends on a storage capacity feature to avoid voltage limit violation. In addition, a linear quadratic regulator is employed as a voltage controller to track the reference grid voltage that is obtained from the proposed P/V droop control strategy. In the proposed control method, a long-term energy storage element, such as a battery, also can be used to regulate voltage and deliver insufficient power in a microgrid. It is concluded that the proposed control method exhibits an effective result in voltage and power issue during transient.

A chain is as strong as its weakest link: assessing the consequences of habitat loss and degradation in a long-distance migratory shorebird

The conservation of migratory species represents a major challenge, as they use multiple sites, all contributing in varying degrees in sustaining high survival and reproductive success. There is particular concern for shorebirds of the East Asian-Australasian Flyway (EAAF), where declining numbers of migratory species have mostly been attributed to habitat loss along the East Asian coast. Using a stochastic dynamic programming migration model, we assessed the effect of habitat degradation scenarios along the EAAF on migration behaviour, survival and reproductive success of a long-distance migrating shorebird, the Ruddy Turnstone (Arenaria interpres). Following manipulation of habitat quality through changes in intake rate, we found that changes on the wintering (major non-breeding) ground in South Australia had the highest negative effect on reproductive success and survival. We also identified Taiwan and the Yellow Sea as sites with high importance for reproductive success. Although habitats along the East Asian coastline are currently most threatened from a range of global change processes, we highlight the importance of conserving high-quality shorebird wintering habitat in Australia. This may be of notable importance to trans-equatorial migratory shorebirds, which often make a long non-stop flight from their wintering grounds in order to skip low-latitude sites that typically provide little food.

Integrating goal-oriented and use case-based requirements engineering: the missing link

Combining goal-oriented and use case modeling has been shown as an effective method of requirements engineering. To ensure the quality of such modeled artifacts, a conceptual foundation is needed to govern the process of determining what types of artifacts to be modeled, and how they should be specified and analyzed for 3Cs problems (completeness, consistency and correctness). However, such a foundation is missing in current goal-use case integration approaches. In this paper, we present GUIMeta, a meta-model, to address this problem. GUIMeta consists of three layers. The artifact layer defines the semantics and classification of artifacts and their relationships. The specification layer offers specification rules for each artifact class. The ontology layer allows semantics to be integrated into the entire model. Our promising evaluation shows the suitability of GUIMeta in modeling goals and use cases.

What did they expect? Exploring a link between students’ expectations, attendance and attrition on English language enhancement courses

This article reports on and discusses the findings of an investigationcarried out to explore the expectations of an English language enhancementcourse (ELEC) held by a group of undergraduate students at anAustralian university. For the study, a mixed-methods approach was utilised,with two instruments: a survey with a combination of closed- andopen-ended questions and semi-structured interviews. The research wasguided by the following three questions: (1) What do the students expectto learn on the course? (2) How are they developing their expectations?(3) Are the students’ expectations being met? The literature concerningstudent expectations foregrounds the complexity and multi-faceted natureof the concept, the satisfaction of which can impact on student engagement,satisfaction, performance, retention and attrition. Findings showthat the participants’ expectations of the course content and teachingstaff were largely met; nonetheless, a lack of class attendance was notedthroughout. Expectations were reported to have been developed largelythrough consultation with previous students of the course (43 per cent)and information materials provided by the university (42 per cent). Thearticle concludes with a discussion regarding the implications of thefindings for universities and education providers both in Australia andabroad.

Sulfur transfer and activation by ubiquitin-like modifier system Uba4•Urm1 link protein urmylation and tRNA thiolation in yeast

Urm1 is a unique dual-function member of the ubiquitin protein family and conserved from yeast to man. It acts both as a protein modifier in ubiquitin-like urmylation and as a sulfur donor for tRNA thiolation, which in concert with the Elongator pathway forms 5-methoxy-carbonyl-methyl-2-thio (mcm5s2) modified wobble uridines (U34) in anticodons. Using Saccharomyces cerevisiae as a model to study a relationship between these two functions, we examined whether cultivation temperature and sulfur supply previously implicated in the tRNA thiolation branch of the URM1 pathway also contribute to proper urmylation. Monitoring Urm1 conjugation, we found urmylation of the peroxiredoxin Ahp1 is suppressed either at elevated cultivation temperatures or under sulfur starvation. In line with this, mutants with sulfur transfer defects that are linked to enzymes (Tum1, Uba4) required for Urm1 activation by thiocarboxylation (Urm1-COSH) were found to maintain drastically reduced levels of Ahp1 urmylation and mcm5s2U34 modification. Moreover, as revealed by site specific mutagenesis, the Stransfer rhodanese domain (RHD) in the E1-like activator (Uba4) crucial for Urm1-COSH formation is critical but not essential for protein urmylation and tRNA thiolation. In sum, sulfur supply, transfer and activation chemically link protein urmylation and tRNA thiolation. These are features that distinguish the ubiquitin-like modifier system Uba4•Urm1 from canonical ubiquitin family members and will help elucidate whether, in addition to their mechanistic links, the protein and tRNA modification branches of the URM1 pathway may also relate in function to one another.

Simulation by discrete mass modeling of offshore wind turbine system with DC link

This paper presents an integrated model for an offshore wind turbine taking into consideration a contribution for the marine wave and wind speed with perturbations influences on the power quality of current injected into the electric grid. The paper deals with the simulation of one floating offshore wind turbine equipped with a permanent magnet synchronous generator, and a two-level converter connected to an onshore electric grid. The use of discrete mass modeling is accessed in order to reveal by computing the total harmonic distortion on how the perturbations of the captured energy are attenuated at the electric grid injection point. Two torque actions are considered for the three-mass modeling, the aerodynamic on the flexible part and on the rigid part of the blades. Also, a torque due to the influence of marine waves in deep water is considered. Proportional integral fractional-order control supports the control strategy. A comparison between the drive train models is presented.