Context detection and abstraction in smart environments

Context-aware computing is currently considered the most promising approach to overcome information overload and to speed up access to relevant information and services. Context-awareness may be derived from many sources, including user profile and preferences, network information, sensor analysis; usually context-awareness relies on the ability of computing devices to interact with the physical world, i.e. with the natural and artificial objects hosted within the "environment”. Ideally, context-aware applications should not be intrusive and should be able to react according to user’s context, with minimum user effort. Context is an application dependent multidimensional space and the location is an important part of it since the very beginning. Location can be used to guide applications, in providing information or functions that are most appropriate for a specific position. Hence location systems play a crucial role. There are several technologies and systems for computing location to a vary degree of accuracy and tailored for specific space model, i.e. indoors or outdoors, structured spaces or unstructured spaces. The research challenge faced by this thesis is related to pedestrian positioning in heterogeneous environments. Particularly, the focus will be on pedestrian identification, localization, orientation and activity recognition. This research was mainly carried out within the “mobile and ambient systems” workgroup of EPOCH, a 6FP NoE on the application of ICT to Cultural Heritage. Therefore applications in Cultural Heritage sites were the main target of the context-aware services discussed. Cultural Heritage sites are considered significant test-beds in Context-aware computing for many reasons. For example building a smart environment in museums or in protected sites is a challenging task, because localization and tracking are usually based on technologies that are difficult to hide or harmonize within the environment. Therefore it is expected that the experience made with this research may be useful also in domains other than Cultural Heritage. This work presents three different approaches to the pedestrian identification, positioning and tracking: Pedestrian navigation by means of a wearable inertial sensing platform assisted by the vision based tracking system for initial settings an real-time calibration; Pedestrian navigation by means of a wearable inertial sensing platform augmented with GPS measurements; Pedestrian identification and tracking, combining the vision based tracking system with WiFi localization. The proposed localization systems have been mainly used to enhance Cultural Heritage applications in providing information and services depending on the user’s actual context, in particular depending on the user’s location.

Uniquitous internet middleware: architecture design and prototype evaluation

Technology advances in recent years have dramatically changed the way users exploit contents and services available on the Internet, by enforcing pervasive and mobile computing scenarios and enabling access to networked resources almost from everywhere, at anytime, and independently of the device in use. In addition, people increasingly require to customize their experience, by exploiting specific device capabilities and limitations, inherent features of the communication channel in use, and interaction paradigms that significantly differ from the traditional request/response one. So-called Ubiquitous Internet scenario calls for solutions that address many different challenges, such as device mobility, session management, content adaptation, context-awareness and the provisioning of multimodal interfaces. Moreover, new service opportunities demand simple and effective ways to integrate existing resources into new and value added applications, that can also undergo run-time modifications, according to ever-changing execution conditions. Despite service-oriented architectural models are gaining momentum to tame the increasing complexity of composing and orchestrating distributed and heterogeneous functionalities, existing solutions generally lack a unified approach and only provide support for specific Ubiquitous Internet aspects. Moreover, they usually target rather static scenarios and scarcely support the dynamic nature of pervasive access to Internet resources, that can make existing compositions soon become obsolete or inadequate, hence in need of reconfiguration. This thesis proposes a novel middleware approach to comprehensively deal with Ubiquitous Internet facets and assist in establishing innovative application scenarios. We claim that a truly viable ubiquity support infrastructure must neatly decouple distributed resources to integrate and push any kind of content-related logic outside its core layers, by keeping only management and coordination responsibilities. Furthermore, we promote an innovative, open, and dynamic resource composition model that allows to easily describe and enforce complex scenario requirements, and to suitably react to changes in the execution conditions.

Rapporti fra fattori ambientali e proteine di parete in Bifidobacterium

The normal gut microbiota has several important functions in host physiology and metabolism, and plays a key role in health and disease. Bifidobacteria, which are indigenous components of gastrointestinal microbiota, may play an important role in maintaining the well-being of the host although its precise function is very difficult to study. Its physiological and biochemical activities are controlled by many factors, particularly diet and environment. Adherence and colonization capacity are considered as contributing factors for immune modulation, pathogen exclusion, and enhanced contact with the mucosa. In this way, bifidobacteria would fortify the microbiota that forms an integral part of the mucosal barrier and colonization resistance against pathogens. Bifidobacteria are not only subjected to stressful conditions in industrial processes, but also in nature, where the ability to respond quickly to stress is essential for survival. Bifidobacteria, like other microorganisms, have evolved sensing systems for/and defences against stress that allow them to withstand harsh conditions and sudden environmental changes. Bacterial stress responses rely on the coordinated expression of genes that alter various cellular processes and structures (e.g. DNA metabolism, housekeeping genes, cell-wall proteins, membrane composition) and act in concert to improve bacterial stress tolerance. The integration of these stress responses is accomplished by regulatory networks that allow the cell to react rapidly to various and sometimes complex environmental changes. This work examined the effect of important stressful conditions, such as changing pH and osmolarity, on the biosynthesis of cell wall proteins in B. pseudolongum subsp. globosum. These environmental factors all influence heavily the expression of BIFOP (BIFidobacterial Outer Proteins) in the cell-wall and can have an impact in the interaction with host. Also evidence has been collected linking the low concentration of sugar in the culture medium with the presence or absence of extracromosomal DNA.

Semantic coordination through programmable Tuple spaces

Two of the main features of today complex software systems like pervasive computing systems and Internet-based applications are distribution and openness. Distribution revolves around three orthogonal dimensions: (i) distribution of control|systems are characterised by several independent computational entities and devices, each representing an autonomous and proactive locus of control; (ii) spatial distribution|entities and devices are physically distributed and connected in a global (such as the Internet) or local network; and (iii) temporal distribution|interacting system components come and go over time, and are not required to be available for interaction at the same time. Openness deals with the heterogeneity and dynamism of system components: complex computational systems are open to the integration of diverse components, heterogeneous in terms of architecture and technology, and are dynamic since they allow components to be updated, added, or removed while the system is running. The engineering of open and distributed computational systems mandates for the adoption of a software infrastructure whose underlying model and technology could provide the required level of uncoupling among system components. This is the main motivation behind current research trends in the area of coordination middleware to exploit tuple-based coordination models in the engineering of complex software systems, since they intrinsically provide coordinated components with communication uncoupling and further details in the references therein. An additional daunting challenge for tuple-based models comes from knowledge-intensive application scenarios, namely, scenarios where most of the activities are based on knowledge in some form|and where knowledge becomes the prominent means by which systems get coordinated. Handling knowledge in tuple-based systems induces problems in terms of syntax - e.g., two tuples containing the same data may not match due to differences in the tuple structure - and (mostly) of semantics|e.g., two tuples representing the same information may not match based on a dierent syntax adopted. Till now, the problem has been faced by exploiting tuple-based coordination within a middleware for knowledge intensive environments: e.g., experiments with tuple-based coordination within a Semantic Web middleware (surveys analogous approaches). However, they appear to be designed to tackle the design of coordination for specic application contexts like Semantic Web and Semantic Web Services, and they result in a rather involved extension of the tuple space model. The main goal of this thesis was to conceive a more general approach to semantic coordination. In particular, it was developed the model and technology of semantic tuple centres. It is adopted the tuple centre model as main coordination abstraction to manage system interactions. A tuple centre can be seen as a programmable tuple space, i.e. an extension of a Linda tuple space, where the behaviour of the tuple space can be programmed so as to react to interaction events. By encapsulating coordination laws within coordination media, tuple centres promote coordination uncoupling among coordinated components. Then, the tuple centre model was semantically enriched: a main design choice in this work was to try not to completely redesign the existing syntactic tuple space model, but rather provide a smooth extension that { although supporting semantic reasoning { keep the simplicity of tuple and tuple matching as easier as possible. By encapsulating the semantic representation of the domain of discourse within coordination media, semantic tuple centres promote semantic uncoupling among coordinated components. The main contributions of the thesis are: (i) the design of the semantic tuple centre model; (ii) the implementation and evaluation of the model based on an existent coordination infrastructure; (iii) a view of the application scenarios in which semantic tuple centres seem to be suitable as coordination media.

Polymorphs solvates and co-crystals of molecular materials

The scope of my research project is to produce and characterize new crystalline forms of organic compounds, focusing the attention on co-crystals and then transferring these notions on APIs to produce co-crystals of potential interest in the pharmaceutical field. In the first part of this work co-crystallization experiments were performed using as building blocks the family of aliphatic dicarboxylic acids HOOC-(CH2)n-COOH, with n= 2-8. This class of compounds has always been an object of study because it is characterized by an interesting phenomenon of alternation of melting points: the acids with an even number of carbon atoms show a melting point higher than those with an odd one. The acids were co-crystallized with four dipyridyl molecules (formed by two pyridine rings with a different number of bridging carbon atoms) through the formation of intermolecular interactions N•••(H)O. The bases used were: 4,4’-bipyridine (BPY), 1,2-bis(4-pyridyl)ethane (BPA), 1,2-(di-4-pyridyl)ethylene (BPE) and 1,2-bis(4-pyridyl)propane (BPP). The co-crystals obtained by solution synthesis were characterized by different solid-state techniques to determine the structure and to see how the melting points in co-crystals change. In the second part of this study we tried to obtain new crystal forms of compounds of pharmaceutical interest. The APIs studied are: O-desmethylvenlafaxine, Lidocaine, Nalidixic Acid and Sulfadiazine. Each API was subjected to Polymorph Screening and Salt/Co-crystal Screening experiments to identify new crystal forms characterized by different properties. In a typical Salt/Co-crystal Screening the sample was made to react with a co-former (solid or liquid) through different methods: crystallization by solution, grinding, kneading and solid-gas reactions. The new crystal forms obtained were characterized by different solid state techniques (X-ray single crystal diffraction, X-ray powder diffraction, Differential Scanning Calorimetry, Thermogravimetric Analysis, Evolved gas analysis, FT-IR – ATR, Solid State N.M.R).

Collaborative Change: Environmental Jolt, Network (Re)Design and Firm Performance

Motivated by the need to understand which are the underlying forces that trigger network evolution, we develop a multilevel theoretical and empirically testable model to examine the relationship between changes in the external environment and network change. We refer to network change as the dissolution or replacement of an interorganizational tie, adding also the case of the formation of new ties with new or preexisting partners. Previous research has paid scant attention to the organizational consequences of quantum change enveloping entire industries in favor of an emphasis on continuous change. To highlight radical change we introduce the concept of environmental jolt. The September 11 terrorist attacks provide us with a natural experiment to test our hypotheses on the antecedents and the consequences of network change. Since network change can be explained at multiple levels, we incorporate firm-level variables as moderators. The empirical setting is the global airline industry, which can be regarded as a constantly changing network of alliances. The study reveals that firms react to environmental jolts by forming homophilous ties and transitive triads as opposed to the non jolt periods. Moreover, we find that, all else being equal, firms that adopt a brokerage posture will have positive returns. However, we find that in the face of an environmental jolt brokerage relates negatively to firm performance. Furthermore, we find that the negative relationship between brokerage and performance during an environmental jolt is more significant for larger firms. Our findings suggest that jolts are an important predictor of network change, that they significantly affect operational returns and should be thus incorporated in studies of network dynamics.

Neuroinflammation and the role of glia: relevance for neurodegenerative and neurosupportive roles

Inflammation is thought to contribute to the pathogenesis of neurodegenerative diseases. Among the resident population of cells in the brain, astroglia have been suggested to actively participate in the induction and regulation of neuroinflammation by controlling the secretion of local mediators. However, the initial cellular mechanisms by which astrocytes react to pro-inflammatory molecules are still unclear. Our study identified mitochondria as highly sensitive organelles that rapidly respond to inflammatory stimuli. Time-lapse video microscopy revealed that mitochondrial morphology, dynamics and motility are drastically altered upon inflammation, resulting in perinuclear clustering of mitochondria. These mitochondrial rearrangements are accompanied by an increased formation of reactive oxygen species and a recruitment of autophagic vacuoles. 24 to 48 hours after the acute inflammatory stimulus, however, the mitochondrial network is re-established. Strikingly, the recovery of a tubular mitochondrial network is abolished in astrocytes with a defective autophagic response, indicating that activation of autophagy is required to restore mitochondrial dynamics. By employing co-cultivation assays we observed that primary cortical neurons undergo degeneration in the presence of inflamed astrocytes. However, this effect was not observed when the primary neurons were grown in conditioned medium derived from inflamed astrocytes, suggesting that a direct contact between astrocytes and neurons mediates neuronal dysfunction upon inflammation. Our results suggest that astrocytes react to inflammatory stimuli by transiently rearranging their mitochondria, a process that involves the autophagic machinery.

Alkylidene malonates and acetoacetates as intermediates for the preparation of bioactive molecules

In this thesis we investigated the versatility and the potential applications of different kinds of alkylidene malonates, acetoacetates, malonamides and acetoacetoamides. Our research group devoted great attention to this kind of compounds since alkylidenes can be considered important intermediates in the synthesis of several scaffolds, to be inserted into molecules of potential biological and pharmaceutical interest. The increasing use of alkylidenes is due to their ability to react as unsaturated electrophiles and to the possibility to exploit them as intermediates for the introduction of different kind of functionalities.The preparation of alkylidene malonates, acetoacetates, malonamides and acetoacetoamides is presented in chapter 1. This section deals with different preparation methods of alkylidenes that we developed during the last few years and to the technologies involved for each synthetic protocol. The reactivity that allowed to use the alkylidenes as intermediates in the synthesis of scaffolds for biologically active compounds is shown in chapter 2. In particular, we will discuss the most important reactions used to obtain the desired molecules, and we will focus on the most interesting aspects of these latter ones. Finally, chapter 3 will illustrate the potential applications and the related syntheses of potential bioactive compounds. The synthesized molecules find application in several fields and for this reason we considered each class of compounds in its related branch of interest.

Effects of temperature and acidity on Mediterranean benthic calcifiers, in the face of globale climate change

The Mediterranean Sea is expected to react faster to global change compared to the ocean and is already showing more pronounced warming and acidification rates. A study performed along the Italian western coast showed that porosity of the skeleton increases with temperature in the zooxanthellate (i.e. symbiotic with unicellular algae named zooxanthellae) solitary scleractinian Balanophyllia europaea while it does not vary with temperature in the solitary non-zooxanthellate Leptopsammia pruvoti. These results were confirmed by another study that indicated that the increase in porosity was accompanied by an increase of the fraction of the largest pores in the pore-space, perhaps due to an inhibition of the photosynthetic process at elevated temperatures, causing an attenuation of calcification. B. europaea, L. pruvoti and the colonial non-zooxanthellate Astroides calycularis, transplanted along a natural pH gradient, showed that high temperature exacerbated the negative effect of lowered pH on their mortality rates. The growth of the zooxanthellate species did not react to reduced pH, while the growth of the two non-zooxanthellate species was negatively affected. Reduced abundance of naturally occurring B. europaea, a mollusk, a calcifying and a non-calcifying macroalgae were observed along the gradient while no variation was seen in the abundance of a calcifying green alga. With decreasing pH, the mineralogy of the coral and mollusk did not change, while the two calcifying algae decreased the content of aragonite in favor of the less soluble calcium sulphates and whewellite (calcium oxalate), possibly as a mechanism of phenotypic plasticity. Increased values of porosity and macroporosity with CO2 were observed in B. europaea specimens, indicating reduces the resistance of its skeletons to mechanical stresses with increasing acidity. These findings, added to the negative effect of temperature on various biological parameters, generate concern on the sensitivity of this zooxanthellate species to the envisaged global climate change scenarios.

Micro and Macro essays in Applied Fiscal Policy

This thesis analysis micro and macro aspect of applied fiscal policy issues. The first chapter investigates the extent to which local budget spending composition reacts to fiscal rules variations. I consider the budget of Italian municipalities and exploit specific changes in the Domestic Stability Pact’s rules, to perform a difference-in-discontinuities analysis. The results show that imposing a cap on the total amount of consumption and investment is not as binding as two caps, one for consumption and a different one for investment. More specifically, consumption is triggered by changes in wages and services spending, while investment relies on infrastructure movements. In addition, there is evidence that when an increase in investment is achieved, there is also a higher budget deficit level. The second chapter intends to analyze the extent to which fiscal policy shocks are able to affect macrovariables during business cycle fluctuations, differentiating among three intervention channels: public taxation, consumption and investment. The econometric methodology implemented is a Panel Vector Autoregressive model with a structural characterization. The results show that fiscal shocks have different multipliers in relation to expansion or contraction periods: output does not react during good times while there are significant effects in bad ones. The third chapter evaluates the effects of fiscal policy announcements by the Italian government on the long-term sovereign bond spread of Italy relative to Germany. After collecting data on relevant fiscal policy announcements, we perform an econometric comparative analysis between the three cabinets that followed one another during the period 2009-2013. The results suggest that only fiscal policy announcements made by members of Monti’s cabinet have been effective in influencing significantly the Italian spread in the expected direction, revealing a remarkable credibility gap between Berlusconi’s and Letta’s governments with respect to Monti’s administration.

Medical Malpractice in Public Healthcare Systems: An Empirical Investigation of Scheduled Damages

In the last decades, medical malpractice has been framed as one of the most critical issues for healthcare providers and health policy, holding a central role on both the policy agenda and public debate. The Law and Economics literature has devoted much attention to medical malpractice and to the investigation of the impact of malpractice reforms. Nonetheless, some reforms have been much less empirically studied as in the case of schedules, and their effects remain highly debated. The present work seeks to contribute to the study of medical malpractice and of schedules of noneconomic damages in a civil law country with a public national health system, using Italy as case study. Besides considering schedules and exploiting a quasi-experimental setting, the novelty of our contribution consists in the inclusion of the performance of the judiciary (measured as courts’ civil backlog) in the empirical analysis. The empirical analysis is twofold. First, it investigates how limiting compensations for pain and suffering through schedules impacts on the malpractice insurance market in terms of presence of private insurers and of premiums applied. Second, it examines whether, and to what extent, healthcare providers react to the implementation of this policy in terms of both levels and composition of the medical treatments offered. Our findings show that the introduction of schedules increases the presence of insurers only in inefficient courts, while it does not produce significant effects on paid premiums. Judicial inefficiency is attractive to insurers for average values of schedules penetration of the market, with an increasing positive impact of inefficiency as the territorial coverage of schedules increases. Moreover, the implementation of schedules tends to reduce the use of defensive practices on the part of clinicians, but the magnitude of this impact is ultimately determined by the actual degree of backlog of the court implementing schedules.