Development of an instrumentation system embedded on FPGA for real time measurement of mechanical vibrations in rotating machinery

The real-time monitoring of events in an industrial plant is vital, to monitor the actual conditions of operation of the machinery responsible for the manufacturing process. A predictive maintenance program includes condition monitoring of the rotating machinery, to anticipate possible conditions of failure. To increase the operational reliability it is thus necessary an efficient tool to analyze and monitor the equipments, in real-time, and enabling the detection of e.g. incipient faults in bearings. To fulfill these requirements some innovations have become frequent, namely the inclusion of vibration sensors or stator current sensors. These innovations enable the development of new design methodologies that take into account the ease of future modifications, upgrades, and replacement of the monitored machine, as well as expansion of the monitoring system. This paper presents the development, implementation and testing of an instrument for vibration monitoring, as a possible solution to embed in industrial environment. The digital control system is based on an FPGA, and its configuration with an open hardware design tool is described. Special focus is given to the area of fault detection in rolling bearings. © 2012 IEEE.

Antifungal activity of flavonoids from Heteropterys byrsonimifolia and a commercial source against Aspergillus ochraceus: In silico interactions of these compounds with a protein kinase

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Development of hydrophilic nanocarriers for the charged form of the local anesthetic articaine

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Joint NOD2/RIPK2 Signaling Regulates IL-17 Axis and Contributes to the Development of Experimental Arthritis

Intracellular pattern recognition receptors such as the nucleotide-binding oligomerization domain (NOD)-like receptors family members are key for innate immune recognition of microbial infection and may play important roles in the development of inflammatory diseases, including rheumatic diseases. In this study, we evaluated the role of NOD1 and NOD2 on development of experimental arthritis. Ag-induced arthritis was generated in wild-type, NOD1(-/-)!, NOD2(-/-), or receptor-interacting serine-threonine kinase 2(-/-) (RIPK2(-/-)) immunized mice challenged intra-articularly with methylated BSA. Nociception was determined by electronic Von Frey test. Neutrophil recruitment and histopathological analysis of proteoglycan lost was evaluated in inflamed joints. Joint levels of inflammatory cytokine/chemokine were measured by ELISA. Cytokine (IL-6 and IL-23) and NOD2 expressions were determined in mice synovial tissue by RT-PCR. The NOD2(-/-) and RIPK2(-/-), but not NOD1(-/-), mice are protected from Ag-induced arthritis, which was characterized by a reduction in neutrophil recruitment, nociception, and cartilage degradation. NOD2/RIPK2 signaling impairment was associated with a reduction in proinflammatory cytokines and chemokines (TNF, IL-1 beta, and CXCL1/KC). IL-17 and IL-17 triggering cytokines (IL-6 and IL-23) were also reduced in the joint, but there is no difference in the percentage of CD4(+) IL-17(+) cells in the lymph node between arthritic wild-type and NOD2(-/-) mice. Altogether, these findings point to a pivotal role of the NOD2/RIPK2 signaling in the onset of experimental arthritis by triggering an IL-17-dependent joint immune response. Therefore, we could propose that NOD2 signaling is a target for the development of new therapies for the control of rheumatoid arthritis. The Journal of Immunology, 2012, 188: 5116-5122.

Design and Characterization of New Luminescent Sensors and Labels

The aim of this Ph.D. project has been the design and characterization of new and more efficient luminescent tools, in particular sensors and labels, for analytical chemistry, medical diagnostics and imaging. Actually both the increasing temporal and spatial resolutions that are demanded by those branches, coupled to a sensitivity that is required to reach the single molecule resolution, can be provided by the wide range of techniques based on luminescence spectroscopy. As far as the development of new chemical sensors is concerned, as chemists we were interested in the preparation of new, efficient, sensing materials. In this context, we kept developing new molecular chemosensors, by exploiting the supramolecular approach, for different classes of analytes. In particular we studied a family of luminescent tetrapodal-hosts based on aminopyridinium units with pyrenyl groups for the detection of anions. These systems exhibited noticeable changes in the photophysical properties, depending on the nature of the anion; in particular, addition of chloride resulted in a conformational change, giving an initial increase in excimeric emission. A good selectivity for dicarboxylic acid was also found. In the search for higher sensitivities, we moved our attention also to systems able to perform amplification effects. In this context we described the metal ion binding properties of three photoactive poly-(arylene ethynylene) co-polymers with different complexing units and we highlighted, for one of them, a ten-fold amplification of the response in case of addition of Zn2+, Cu2+ and Hg2+ ions. In addition, we were able to demonstrate the formation of complexes with Yb3+ an Er3+ and an efficient sensitization of their typical metal centered NIR emission upon excitation of the polymer structure, this feature being of particular interest for their possible applications in optical imaging and in optical amplification for telecommunication purposes. An amplification effect was also observed during this research in silica nanoparticles derivatized with a suitable zinc probe. In this case we were able to prove, for the first time, that nanoparticles can work as “off-on” chemosensors with signal amplification. Fluorescent silica nanoparticles can be thus seen as innovative multicomponent systems in which the organization of photophysically active units gives rise to fruitful collective effects. These precious effects can be exploited for biological imaging, medical diagnostic and therapeutics, as evidenced also by some results reported in this thesis. In particular, the observed amplification effect has been obtained thanks to a suitable organization of molecular probe units onto the surface of the nanoparticles. In the effort of reaching a deeper inside in the mechanisms which lead to the final amplification effects, we also attempted to find a correlation between the synthetic route and the final organization of the active molecules in the silica network, and thus with those mutual interactions between one another which result in the emerging, collective behavior, responsible for the desired signal amplification. In this context, we firstly investigated the process of formation of silica nanoparticles doped with pyrene derivative and we showed that the dyes are not uniformly dispersed inside the silica matrix; thus, core-shell structures can be formed spontaneously in a one step synthesis. Moreover, as far as the design of new labels is concerned, we reported a new synthetic approach to obtain a class of robust, biocompatible silica core-shell nanoparticles able to show a long-term stability. Taking advantage of this new approach we also showed the synthesis and photophysical properties of core-shell NIR absorbing and emitting materials that proved to be very valuable for in-vivo imaging. In general, the dye doped silica nanoparticles prepared in the framework of this project can conjugate unique properties, such as a very high brightness, due to the possibility to include many fluorophores per nanoparticle, high stability, because of the shielding effect of the silica matrix, and, to date, no toxicity, with a simple and low-cost preparation. All these features make these nanostructures suitable to reach the low detection limits that are nowadays required for effective clinical and environmental applications, fulfilling in this way the initial expectations of this research project.

Continuity and Change in New Products

This doctoral dissertation is triggered by an emergent problem: how can firms reinvent themselves? Continuity- and change-oriented decisions fundamentally shape overtime the activities and potential revenues of organizations and other adaptive systems, but both types of actions draw upon limited resources and rely on different organizational routines and capabilities. Most organizations appear to have difficulties in making tradeoffs, so that it is easier to overinvest in one of them than to successfully achieve a mixture of both. Nevertheless, theory and empirical evidence suggest that too little of either may reduce performance, indicating a need to learn more about how organizations reconcile these tensions. In the first paper, I moved from the consideration that rapid changes in competitive environments increasingly require firms to be “ambidextrous” implementing organizational mechanisms and structures that allow continuity- and change-oriented activities to be engaged at the same time. More specifically, I show that continuity- and change-related decisions can’t be confined either inside or outside the firm, but span overtime across distinct decision domains located within and beyond the organizational boundaries. Reconciling static and dynamic perspectives of ambidexterity, I conceptualize a firm’s strategy as a bundle of decisions about product attributes and components of the production team, proposing a multidimensional and dynamic model of structural ambidexterity that explains why and how firms could manage conflicting pressures for continuity and change in the context of new products. In the second study I note how rigorous systematic evidence documenting the success of ambidextrous organizations is lacking, and there has been very little investigation of how firms deal with continuity and change in new products. How to manage the transition form a successful product to another? What to change and what to keep? Incumbents that deal with series of products over time need to update their offerings in order to have the most relevant attributes to prospect clients without disappoint the current customer base. They need to both match and anticipate consumers’ preferences, blending something old with something new to satisfy the current demand and enlarge the herd by appealing to newer audiences. This paper contributes to strategic renewal and ambidexterity-related research with the first empirically assessment of a positive consumer response to ambidexterity in new products. Also, this study provides a practical method to monitor overtime the degree to which a brand or a firm is continuity- or change- oriented and evaluate different strategy profiles across two decision domains that play a pivotal role in new products: product attributes and components of the production team.

Development of newly conceived biomimetic nano-structured biomaterials as scaffolds for bone and osteochondral regeneration

The present research thesis was focused on the development of new biomaterials and devices for application in regenerative medicine, particularly in the repair/regeneration of bone and osteochondral regions affected by degenerative diseases such as Osteoarthritis and Osteoporosis or serious traumas. More specifically, the work was focused on the synthesis and physico-chemical-morphological characterization of: i) a new superparamagnetic apatite phase; ii) new biomimetic superparamagnetic bone and osteochondral scaffolds; iii) new bioactive bone cements for regenerative vertebroplasty. The new bio-devices were designed to exhibit high biomimicry with hard human tissues and with functionality promoting faster tissue repair and improved texturing. In particular, recent trends in tissue regeneration indicate magnetism as a new tool to stimulate cells towards tissue formation and organization; in this perspective a new superparamagnetic apatite was synthesized by doping apatite lattice with di-and trivalent iron ions during synthesis. This finding was the pin to synthesize newly conceived superparamagnetic bone and osteochondral scaffolds by reproducing in laboratory the biological processes yielding the formation of new bone, i.e. the self-assembly/organization of collagen fibrils and heterogeneous nucleation of nanosized, ionically substituted apatite mimicking the mineral part of bone. The new scaffolds can be magnetically switched on/off and function as workstations guiding fast tissue regeneration by minimally invasive and more efficient approaches. Moreover, in the view of specific treatments for patients affected by osteoporosis or traumas involving vertebrae weakening or fracture, the present work was also dedicated to the development of new self-setting injectable pastes based on strontium-substituted calcium phosphates, able to harden in vivo and transform into strontium-substituted hydroxyapatite. The addition of strontium may provide an anti-osteoporotic effect, aiding to restore the physiologic bone turnover. The ceramic-based paste was also added with bio-polymers, able to be progressively resorbed thus creating additional porosity in the cement body that favour cell colonization and osseointegration.

Characterization of optical transduction-based molecular systems and nanoparticles for the development of chemical sensors

With the increasing importance that nanotechnologies have in everyday life, it is not difficult to realize that also a single molecule, if properly designed, can be a device able to perform useful functions: such a chemical species is called chemosensor, that is a molecule of abiotic origin that signals the presence of matter or energy. Signal transduction is the mechanism by which an interaction of a sensor with an analyte yields a measurable form of energy. When dealing with the design of a chemosensor, we need to take into account a “communication requirement” between its three component: the receptor unit, responsible for the selective analyte binding, the spacer, which controls the geometry of the system and modulates the electronic interaction between the receptor and the signalling unit, whose physico-chemical properties change upon complexation. A luminescent chemosensor communicates a variation of the physico-chemical properties of the receptor unit with a luminescence output signal. This thesis work consists in the characterization of new molecular and nanoparticle-based system which can be used as sensitive materials for the construction of new optical transduction devices able to provide information about the concentration of analytes in solution. In particular two direction were taken. The first is to continue in the development of new chemosensors, that is the first step for the construction of reliable and efficient devices, and in particular the work will be focused on chemosensors for metal ions for biomedical and environmental applications. The second is to study more efficient and complex organized systems, such as derivatized silica nanoparticles. These system can potentially have higher sensitivity than molecular systems, and present many advantages, like the possibility to be ratiometric, higher Stokes shifts and lower signal-to-noise ratio.

Modelling and analysis of networked control strategies in smart power distribution grids: development of co-simulation tools

This thesis is focused on Smart Grid applications in medium voltage distribution networks. For the development of new applications it appears useful the availability of simulation tools able to model dynamic behavior of both the power system and the communication network. Such a co-simulation environment would allow the assessment of the feasibility of using a given network technology to support communication-based Smart Grid control schemes on an existing segment of the electrical grid and to determine the range of control schemes that different communications technologies can support. For this reason, is presented a co-simulation platform that has been built by linking the Electromagnetic Transients Program Simulator (EMTP v3.0) with a Telecommunication Network Simulator (OPNET-Riverbed v18.0). The simulator is used to design and analyze a coordinate use of Distributed Energy Resources (DERs) for the voltage/var control (VVC) in distribution network. This thesis is focused control structure based on the use of phase measurement units (PMUs). In order to limit the required reinforcements of the communication infrastructures currently adopted by Distribution Network Operators (DNOs), the study is focused on leader-less MAS schemes that do not assign special coordinating rules to specific agents. Leader-less MAS are expected to produce more uniform communication traffic than centralized approaches that include a moderator agent. Moreover, leader-less MAS are expected to be less affected by limitations and constraint of some communication links. The developed co-simulator has allowed the definition of specific countermeasures against the limitations of the communication network, with particular reference to the latency and loss and information, for both the case of wired and wireless communication networks. Moreover, the co-simulation platform has bee also coupled with a mobility simulator in order to study specific countermeasures against the negative effects on the medium voltage/current distribution network caused by the concurrent connection of electric vehicles.

Development of Solid Oxide Fuel Cell Electrodes with High Conductivity and Enhanced Redox Stability

The intent of this study was the development of new ceramic SOFC anode materials which possess electrical conductivity as well as redox stability.

Calibration process on the study of new antenna array architectures for space communications

This paper introduces novel calibration processes applied to antenna arrays with new architectures and technologies designed to improve the performance of traditional earth stations for satellite communications due to the increasing requirement of data capacity during last decades. Besides, the Radiation Group from the Technical University of Madrid has been working on the development of new antenna arrays based on novel architecture and technologies along many projects as a solution for the ground segment in the early future. Nowadays, the calibration process is an interesting and cutting edge research field in a period of expansion with a lot of work to do for calibration in transmission and also for reception of these novel antennas under development.

A component library to improve the reusability in the development of converged services

The evolution of communications networks to Next Generation Networks (NGN) has encouraged the development of new services. Nowadays, several technologies are being integrated into telecommunications services in order to provide new functionalities, resulting in what are known as converged services. The objective is to adapt the behavior of the services to the necessities of different users, generating customized services. Some of the main technologies involved in their development are those related to the Web. But due to this type of services implies the combination of different technologies, their development is a very complex process that has to be improved to reduce the time and cost required, with the aim of promoting the success of such services. This paper proposes to apply software reuse through the utilization of a component library and presents one focused on ECharts for SIP Servlets (E4SS). It is a framework, based on the SIP Servlet specification, which uses finite state machines for the definition of converged communications services. Also, to promote the use of the library, a methodology is proposed in order to facilitate the integration between the library operations and the software development cycle.

Design, synthesis and development of PDE5 inhibitors

This research project is concerned with the design, synthesis and development of new phosphodiesterase 5 (PDE5) inhibitors with improved selectivities and lower toxicities. Two series of a 5 member and a 6 member ring fused heterocyclic compounds were designed, and synthesized. By alteration of starting materials and fragments, two virtual libraries, each is consisted of close to hundred compounds, were obtained successfully. The screening of sexual stimulation activity with rabbits demonstrated both groups of compounds were able to stimulate rabbit penile erection significantly. The following toxicity studies revealed 2-(substituted-sulfonylphenyl)-imidazo [1,5-a]-1,3,5-triazine-4-(3H)-one group possessed an unacceptable toxicity with oral LD50 about 200mg/kg; while 2-(substituted-sulfonylphenyl)-pyrrolo[2,3-d]pyrimidin-4-one group showed an acceptable toxicity with oral LD50 over 2000mg/kg. The continued bioactivity studies showed yonkenafil, the representative of 2-(substituted-sulfonylphenyl)-pyrrolo[2,3-d]pyrimidin-4-one group, has a better selectivity towards PDE5 and PDE6 than sildenafil and a better overall profile of sexual stimulation on animals than sildenafil. Chronic toxicity studies of yonkenafil further confirmed yonkenafil did not cause any serious side effect and damage on animal models and most actions were explainable. Based on evidences of the above studies, yonkenafil were recommended to enter clinical trials by the regulation authority of China, SFDA. Currently yonkenafil has been through the Phase I clinical trials and ready to progress into Phase II. Hopefully, yonkenafil will provide an alternative to the ED patients in the future.

Nutritional and chemical characterization of food products enriched with biological produced fruits of Vaccinum myrtillus L

Vaccinum myrtillus L. belongs to Ericaceae family, being commonly known for its sweet small fruits: the blueberries. Widely consumed in fresh, these fruits are also used in jams and marmalades due to their digestive and hypoglycemic properties and also due to the presence of several bioactive compounds [!]. Therefore, it has become a very appealing matrix in the development of functional products that, beyond their nutritional properties, will add a long-term beneficial physiological/health effect [2]. In the present work, three novel blueberry based products developed by RBR Foods Company (Portugal), were characterized in terms of their nutritional and chemical properties: carbohydrates, ash, proteins, fat and energetic value (following official methods of food analysis), fatty acids profile (by CG-FID), soluble sugars (by HPLCRI), organic acids (by HPLC-DAD) and tocopherols (by HPLC-fluorescence). The products result from a mixture of the fruits with rose petals (PI), marigold petals (P2) and apple and goji berries (P3). The blueberry fruits were used as control sample. The nutritional profile of the novel products was very similar to the control sample: the carbohydrates were the most abundant macronutrient, followed by proteins and total fat. Regarding sugars, fructose, glucose and sucrose were identified in all the samples. P 1 and P2 didn't show significant differences in comparison to the control, however, P3 revealed a lower concentration of sugars. In terms of fatty acids composition, all the studied samples presented higher contents in polyunsaturated fatty acids, especially due to the contribution of linoleic and alinolenic acids. The results of tocopherols revealed that the control sample only presented two isoforrns of tocopherols, a- and y-tocopherol, being the same observed in P3. However, P 1 revealed the presence of all the isoforrns of tocopherols, while P2 was lacking otocopherol; which is related with the contribution of rose and marigold petals, respectively. The a-tocopherol isoforrn was the most abundant in all the studied samples. Overall, this work contributed to the nutritional characterization of novel blueberry based products and is a part of a wider project that aims the detailed study of these products, namely their potential to be used as functional foods.

Small Business and entrepreneurship policy

There are two key approaches to entrepreneurship, each of which has different implications for small business policy (Danson 2002). The first conceives of entrepreneurship as an economic process and can be traced to the work of Joseph Schumpeter who developed the concept of creative destruction to describe the entrepreneurial process that led to the simultaneous elimination of old industries and activities and the creation of new activities through the commercial application of new ideas. While entrepreneurship as a process of creative destruction might include start up activity amongst small firms, it does not exclusively involve small firms as large firms may contribute to the entrepreneurial process through the generation of new knowledge and by assisting in financing the development of new ideas amongst small firms. Although innovation occurs in large as well as small firms, the literature on small enterprise innovation draws heavily on Schumpeter’s depiction of the central role of the entrepreneur in the process of creative destruction, whereby the economic system is transformed from within and new cycles in economic life emerge in which new industries and markets replace old industries and markets. Schumpeter argued that entrepreneurs drove the process of innovation and that innovation was a stimulus to economic development and involved the development of new products, processes, methods of production or new forms of commercial or financial organisation (Schumpeter 1911). At a time when technological development and structuraleconomic change are occurring at a rapid pace, small firm innovation is seen to be critically important because empirical evidence, although not undisputed, indicates that SMEs make an important contribution to radical innovations in new industries (Nooteboom 1994). The second view of entrepreneurship focuses on the individual entrepreneur more than the entrepreneurial process. The entrepreneur is depicted as an owner of small businesses, and is regarded as having particular personal characteristics such as self-reliance, individual initiative and self-motivation. Entrepreneurs are also considered to have a behavioural orientation towards the exploitation of new ideas and opportunities. They are the risk takers who are able to see an opportunity and pursue it commercially despite the uncertainty of rewards. The capacity to plan, manage and lead is also seen to be identifying characteristics of entrepreneurs. Different small business policy approaches arise from these different perspectives on entrepreneurship. Small business policy approaches that emphasise the process by which new ideas are generated and applied commercially arise from the first and broader view of entrepreneurship. Policies designed to generate a population of risk taking and self-motivated individuals with highly developed management and commercial skills are more in keeping with the second approach, which is focused on the individual entrepreneur rather than the entrepreneurial process.