Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores (Major de Telecomunicações). Faculdade de Engenharia. Universidade do Porto. 2009

Tese de mestrado integrado. Engenharia Informática e Computação. Faculdade de Engenharia. Universidade do Porto. 2010

Sexual behavior is a normative part of adolescence and it is important to understand how familial factors influence Latina/o adolescents’ sexual health. The current study examined two structural equation models (SEM) and the associations between familial cultural values (i.e., familismo and filial piety), maternal and paternal monitoring (i.e., disclosure and solicitation) and Latina/o adolescent’s sexual behavior (i.e., intentions to have sex, sexual behavior, sexual responsibility). A hypothesized SEM examined whether paternal/maternal monitoring mediated the relation between familial cultural values and adolescents’ sexual health, while an alternative SEM examined whether familial cultural values mediated the association between paternal/maternal monitoring and adolescents’ sexual health. Participants included 1,024 Mexican adolescents (54% female) between the ages 12-18. Results showed that the overall hypothesized SEM had excellent fit indices. Filial piety was associated with favorable sexual health outcomes and increased parental monitoring. Maternal disclosure was associated with lower intention to have sex and more sexual responsibility, while paternal solicitation was associated higher intention to have sex. Sex differences were found after conducting a chi-square difference tests and partially constraining the model. For Latino adolescents, paternal child disclosure and solicitation was associated with intentions to have sex. For Latina adolescents, familismo was associated with more maternal disclosure. Mediational analysis showed that for Latino adolescents, more reported filial piety was associated with more paternal solicitation and disclosure, which was then associated with lower and higher intentions to have sex, respectively. The alternative SEM had excellent fit indices, however, no sex differences were found. Mediational analyses were conducted with the unconstrained model while controlling for sex. Mediational pathways showed that maternal disclosure was positively associated with filial piety, which was associated with lower intention to have sex sexual intention and more sexual responsibility. Findings indicate that family cultural values and paternal monitoring may influence Latino adolescent’s intention to have sex. Additionally, filial piety should be considered as a protective factor for Latina/o adolescents’ sexual health. These findings can inform prevention programs targeting Latina/o families. Furthermore, a greater emphasis should be placed on the importance paternal monitoring and filial piety given their associations with Latino adolescents’ sexual health.

Aluminum-nickel (Al-Ni) alloys and Al/Ni bilayers were successfully electrodeposited from AlCl3-EMIM-NiCl2 electrolyte at room temperature. Dissolution of NiCl2 was shown to be favorable in Lewis basic (with molar ratio of AlCl3 < 0.5) AlCl3-EMIM solution. The use of electrochemically active Cu working electrode as opposed to inert W induced additional Cu oxidation and dissolution in the cyclic voltammetry scan. The reduction potentials of Al and Ni were found to be ~ – 0.3 and 0.15 V vs. Al/Al3+ respectively. Increasing [NiCl2] in the electrolyte leads to an increase of Ni concentration in the deposited structures. Dense and well-adherent Al-Ni alloys with Ni concentration up to 17.7 at.% were deposited by potential control. XRD analysis revealed that the deposited Al-Ni exhibit a supersaturated fcc crystalline structure. The visual appearance of the deposits ranged from bright silver, dull silver, grey, to black, where the darker shade typically indicated higher Ni content. SEM analysis revealed that the surface morphology of the deposits ranged from nodular to flake-like structures. Al-Ni alloy typically showed nodular morphology with cauliflower structure. Flake structures, which were independent of substrate roughness, were found to develop under pulsed potential deposition with 1:1 duty ratio. The concentration of Ni in electrodeposited Al-Ni alloys increases nonlinearly with the increase in molarity of NiCl2. Al and Ni contents increase with increasing the time of positive and negative cycle of the pulse respectively. Decreasing the frequency by half resulted in almost double the amount of Ni in the deposited alloy. A smoother substrate increased Ni concentration from 6 to 17.7 at.%. Al/Ni bilayer was successfully deposited in 1.5:1 AlCl3-EMIM containing 0.026 M NiCl2. Deposition of Al on Ni was achieved using constant potential and pulse potential control. The deposition of Ni on Al is complicated since the deposition potential of Ni lies in the vicinity of Al stripping potential thus inducing competition between Ni deposition and Al stripping.

A detailed row by row investigation of major lateral tooth cusp mineralisation, together with the concomitant development of the superior epithelial tissue surrounding the teeth of the chiton Acanthopleura hirtosa has been undertaken using a combination of light microscopy, and scanning and transmission electron microscopy. A holistic approach has been adopted that encompasses observations over a range of spatial scales, from whole radula mineralisation processes to those occurring within individual tooth cusps at various stages of development. In addition, mineralisation in radulae from freshly collected animals has been compared to that of animals maintained for extensive periods within a newly developed iron limited system, which restricts radula mineralisation without impeding the formation of the organic matrix. An evaluation of the iron limitation technique has revealed that maintaining specimens of A. hirtosa within an iron poor environment results in a significant departure from the normal pattern of mineralisation in these animals. As a consequence of iron limitation, there is an obvious increase in the number of unmineralised tooth rows in addition to associated alterations in structure and composition at all stages of tooth development. In normal specimens of A. hirtosa, the onset of mineralisation in the tooth cusps occurs following the prior accumulation of iron at the junction zone and the sudden accumulation of iron containing granules in the cusp epithelium at tooth row 13. The superior epithelium surrounding the tooth cusps undergoes a series of developmental changes leading up to, and following, the onset of mineralisation. In particular, the abundance of mitochondria within the apical cusp epithelium increases, presumably in order to provide the ideal conditions of pH, and thus solubility, needed for the supersaturation of iron and its nucleation at row 13. Once mineralisation has commenced, the microvilli attached to the cusps develop rapidly, and are suggested to do so in order to facilitate the transport of iron, and thereby ensure that a high concentration gradient of this element into the cusps is maintained. The delivery of iron into the cusps occurs from two fronts, the first from the superior epithelium via the posterior surface, and the second from the junction zone via an internal pathway situated along the lepidocrocite boundary between the magnetite and core regions of the tooth. The existence of a plume of elements between this internal mineralisation pathway and the junction zone, provides the first direct evidence that the junction zone is involved in the storage and release of elements for cusp mineralisation. Data from iron limited radulae also indicate that iron continues to be deposited at the junction zone in preference to the superior epithelium or cusps, despite the disruption of mineralisation, highlighting the importance of this region in the mineralisation process. Iron reinstatement experiments have also shown that the internal pathways of iron delivery within the organic matrix remain viable, despite prolonged periods of iron limitation. In addition, the reinstatement of iron has revealed that the plumes, situated between the junction zone and internal mineralising pathway of the cusp, stem from the centre of the plate like junction zone, directly above the stylus canal, a tube like cavity situated within the styli of each major lateral tooth. An in depth study of the stylus canal has revealed that cells within the canal are remarkably similar to those of the epithelium surrounding the cusps, suggesting that this structure may also be involved in the delivery of ions to the junction zone. The stylus canal is shown to be present in the major lateral tooth cusps of 38 chiton species distributed worldwide, and is therefore likely to be a feature common to all chitons. The presence of the canal, and indeed its absence from the bases of all remaining non iron mineralised teeth, irrespective of chiton species, also points strongly to a functional relationship between the stylus canal and tooth cusp mineralisation.

An image analysis method has been developed for Sandvik to determine phasecompositions and characteristic length of the binding phase in cubic Boron Nitride(cBN)-composites with low contents of cBN (35-75%).The method consists of taking pictures with a Scanning Electron Microscope,gathering elemental data with X-ray Diffraction (XRD) as well as Energy-dispersiveX-ray Spectroscopy (EDS) and finally using a Matlab program developed for this workto calculate phase compositions and statistical data from the characteristic length ofthe binding phase.Using these methods four different phases were identified in the samples: Blackparticles, most likely made of cBN. A dark gray phase around the black particles, thatconsists of Al-compounds. A light grey binding phase, consisting of TiN or Ti(C,N).Finally there were small traces of white particles which were identified as a product ofabrasive action on cermet milling bodies added during the milling.Mean value, standard deviation and median of the characteristic length of the bindingphase was calculated. For all samples the median value was consistent, sometimeseven being identical for the analyzed sites. This indicates that the binding phase wasevenly distributed across almost all samples.

Objectives: To evaluate the effects of ear points pressing at ear meridian points on obesity-related parameters( body weight, body fat, body mass index, waist, hip circumferences, and WC/HC ratio) between treatment and control groups, and we also apply the Self-Determination Theory to discuss the relationship between motivation and performance of body weight control. Methods: The study was an cross over open-parallel randomized control trial and the sample consisted of 189 volunteers who were randomly divided into two groups and the baseline characteristics were similar. In the experimental (immediate treatment) group (n=93), ear points pressing at five ear meridian points and lifestyle education were applied, while volunteers in the control (delay treatment) group (n=96) just receive lifestyle education in the first 8 weeks. At baseline, 24th, 32nd and each week of the sixteen weeks study, the outcomes mentioned above were examined in all volunteers, and related SDT questionnaires were checked during the period of 32 weeks study. Results: The result showed a statistically significant drop in BW, BMI, Waist circumference and Hip circumference during the 32 weeks in experimental (immediate treatment) and control (delay treatment) group, and better effect while using ear points pressing in the same group. But, no significant differences were found between the two groups. A SEM analysis showed that autonomous support, relatedness and original autonomy can get better competence and was related to positive consequences in BW control. And it was relative an adequate model to test the self determination theory. Conclusion: Even though the result showed a statistically significant drop in BW, BMI, WC, HC during the 32 weeks treatment in experimental (immediate treatment) and control (delay treatment) groups, and better effect while using ear points pressing in the same group. But, no statistical significance change in BW related parameters were found between the two groups. Further studies are needed to detect the effect of ear points pressing and model fit of SDT application by increasing research time, and sample sizes.

Electronic customer relationship management (e-CRM) emerges from the Internet and web technology to facilitate the CRM implementation. It focuses on internet- or web-based interaction between companies and their customers. Especially, e-CRM enables service sectors to provide appropriate services and products to satisfy the customers so as to retain customer royalty and enhance customer profitability. This research is to explore the key research issues of e-CRM performance influence. A research model is proposed based on the widely applied technology- organization-environment (TOE) framework. Survey data from the questionnaire are collected to empirically assess our research model. With the structural equation modeling (SEM) analysis, the results show that e-CRM technology and organizational support are positively related to the e-CRM performance, while environmental pressure, though a drive to e-CRM adoption, does not impact the performance. More interestingly, it is observed that organizational support has a greater impact than e-CRM technology adoption. It is always a good principle to care customers¡¦ relationship more from human nature perspectives than from technology-oriented considerations. Also, in the aspect of organizational support, skilled and knowledgeable e-CRM personnel are the most important impacting factor among others. Finally, the contributions of our research lie in that not only the results can provide researchers a good starting point for e-CRM studies, but also can they provide practitioners of service sectors in Taiwan a good reference.

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Diamond-Like Carbon (DLC) films have been deposited on ITO glass substrate. DLC thin film was electrodeposited at low DC potential using a mixture of acetic acid and DI water. The DLC film deposition parameters include DC potential, deposited temperature, the concentration of electrolyte were used to study the characteristics of DLC film measured by the Ellipsometer, XPS, SEM and Raman spectroscopy in detail. The Raman spectra shows two peaks located near 1358cm-1 and 1580cm-1 assigned as the characteristics peaks of DLC films. That is an evidence for DLC film deposited successfully on ITO glass. Scanning electron microscopy (SEM) can make insight into accurately the surface morphology and uniformity of DLC films so as used to grow the best quality of DLC films. From the variations of the I-t curve and the surface morphology observed by SEM, the properties of DLC film depend on a verity of growth parameters such as applied voltage, the concentration of electrolyte and deposition temperature. The shift of G-peak increase with the applied voltage, and the sp2/sp3 ratio of the content C1s decreases with the applied voltage. Finally, based on the I-t curve and results of SEM, XPS, Raman, and Ellipsometer for n, k coefficients measured, we obtain a deeply understanding for the growth conditions of DLC films and their surface morphology. We achieve the consistent results between various measurements. Finally, the optimizing growth of DLC film is to be studied and discussed in future