Tese de mestrado. Mestrado em Engenharia de Segurança e Higiene Ocupacionais. Faculdade de Engenharia. Universidade do Porto. 2012

Sexually transmitted diseases (STDs) continue to remain a public health concern in the United States, especially among young people. Levels of knowledge with regard to STDs have been investigated in prior research; however, these investigations have been limited primarily to older adolescents and young adults. Grounded in the social cognitive and subjective culture theories, this quantitative, cross-sectional study assessed STD knowledge (other than HIV/AIDS) among 7th grade students attending a public middle school in the United States. Demographic differences (age, gender, and ethnicity) in STD knowledge were examined to determine if these demographic variables predict STD knowledge scores and if the Sexually Transmitted Disease Knowledge Questionnaire (STD-KQ) is a valid and reliable instrument among this study population. Chi-square analysis demonstrated that STD knowledge scores significantly differed by age only: Twelve-year-olds had higher STD scores than did 13-year-olds, contrary to research in older adolescents, which may be the result of confounding factors that warrant further investigation. Multiple regression analysis showed that age, gender, and ethnicity were not associated with STD knowledge scores. The STD-KQ was found to have face validity as well as high consistency and reliability among all questions related to STDs other than HIV/AIDS using Crohnbach's alpha. Content validity for individual STD-KQ items was shown using Lawshe's content validity ratio and subject matter experts. Results of the study support positive social change and highlight the need for earlier STD education, other than HIV/AIDS, with middle school children and the need to examine other factors that may impact STD knowledge within this age group.

At Saab Aerospace in Linköping, components for measurement systems to the fighter aircraft JAS 39 Gripen are developed. In this activity you sometimes want to record the traffic transmitted on the data busses that connects different sys-tems. This traffic on the data busses is using the military standard MIL-STD-1553. This project has aimed to create a system for recording and sending 1553-data. The system is used on an ordinary personal computer, equipped with a recon- figurable I/O card that among others has a programmable logic circuit (FPGA). The recorded data are stored on a hard drive. The system has a graphical user interface, where the user can configure different methods of filtering the data, and other preferences. The completed system has currently the capacity to record one channel. This works excellent and the system basically meets all the requirements stated at the start of the project. By using this system instead of the commercial available systems on the market one will get a competitive alternative. If the system where to be developed further, with more channels, it would get even more price worth. Both in case of price per channel, but also in functionality. This is because it is possible to design exactly the functions the user demands. But the current version is already fully functional and competitive compared to commercial systems.

<p>At Saab Aerospace in Linköping, components for measurement systems to the fighter aircraft JAS 39 Gripen are developed. In this activity you sometimes want to record the traffic transmitted on the data busses that connects different sys-tems. This traffic on the data busses is using the military standard MIL-STD-1553. </p><p>This project has aimed to create a system for recording and sending 1553-data. The system is used on an ordinary personal computer, equipped with a recon- figurable I/O card that among others has a programmable logic circuit (FPGA). The recorded data are stored on a hard drive. The system has a graphical user interface, where the user can configure different methods of filtering the data, and other preferences. </p><p>The completed system has currently the capacity to record one channel. This works excellent and the system basically meets all the requirements stated at the start of the project. By using this system instead of the commercial available systems on the market one will get a competitive alternative. If the system where to be developed further, with more channels, it would get even more price worth. Both in case of price per channel, but also in functionality. This is because it is possible to design exactly the functions the user demands. But the current version is already fully functional and competitive compared to commercial systems.</p>

Le Ga1NAc est présent dans un grand nombre de glycoprotéines, protéoglycanes et glycolipides. Il est le sucre immunodominant des antigènes de groupes sanguins et oncofoetaux qui sont des cibles thérapeutiques. Cependant, la synthèse par voie chimique de ces glycoconjugués à Ga1NAc est longue et coûteuse. In vivo, le Ga1NAc est incorporé par des Ga1NActransférases, enzymes spécifiques qui transfèrent le Ga1NAc de l'UDP-GaINAc sur un substrat accepteur. Mais la synthèse chimio enzymatique des glycanes est freinée par l'obtention difficile de quantités importantes d'UDP-Ga1NAc.<br />Nous avons mis au point un système de synthèse chimio enzymatique de glycoconjugués à Ga1NAc qui utilise 4 enzymes et des substrats simples comme le Ga1NAc, l'UTP et la créatine-P. Ce système permet la synthèse rapide et efficace de glycopeptides et d'oligosaccharides à GaINAc ; il a été utilisé pour glycosyler l'antigène MUC1 et nous avons pu évaluer la réponse immunitaire murine contre la petite glycoprotéine obtenue.<br />Le système de synthèse d'UDP-Ga1NAc peut accepter certains dérivés de Ga1NAc et permettre ainsi la synthèse d'analogues d'UDP-Ga1NAc. Ces molécules sont des sondes appréciables pour étudier l'interaction entre substrats et enzymes par les techniques physicochimiques comme la STDNMR.

Costa Rica has been a popular tourist destination for decades, and is currently the second largest industry in the country. With so many tourists coming into the country, Costa Rica provides a rich environment within which to examine sex tourism. Costa Rica is a known destination for male sex tourists hoping to experience legal prostitution or child prostitution. Although it is lesser known, female sex tourism also occurs in Costa Rica. Female sex tourism occurs in the form of pseudo-romantic relationships between female tourists and Costa Rican men working in the tourist industry. These people spend a great deal of time together on tour, and relationships occur frequently. Men are seeking interesting sexual exploration, while women tend to be looking for the "Latin Lover." These relationships are not characteristic of prostitution, as no goods or services are exchanged for sex. These relationships may best be characterized as romantic.

In the United States, the rates of unplanned pregnancies and sexually transmitted diseases, including HIV infection, caused by unprotected sex is alarmingly high. Adverse outcomes of unprotected sexual intercourse continue to be a burden, not only for affected adolescents but for the community at large. Using data from the National Longitudinal Study of Adolescent Health, this study applied the PRECEDE model as a means to identify those salient risk factors and risk conditions of sex initiation and engagement in unprotected sex among adolescent students. Results showed that 52.6% of the students have had sexual intercourse and 54.5% of sexually experienced students reported inconsistent condom use during sexual intercourse. Logistic regression analysis showed that risks factors for having had sexual intercourse differ from those for having engaged in unprotected sex in sexually experienced students. Furthermore, these factors also differed between male and female students. Only students’ age and perceived hardships related to pregnancy were found to be common risk factors for both outcomes in both sex groups. Results suggest that the PRECEDE is a practical tool to aid program planners identify the intervention priorities most relevant to their target populations.

The purpose of this study was to determine: * what the influence of attitude is on the mathematical achievement of the standerd 8 pupil, * which factors contribute mainly to the attitude of the standard 8 pupil towards mathematics. The literature study defined the concept "attitude" as widely as possible. The relationship between attitude and academic achievement was discussed and special reference was given to mathematics achievement. In the literature study factors which can influence mathematical achievement were also discussed. Special reference was given to: * cognitive and non-cognitive factors, * factors referring to the parents, * factors referring to the school situation, * the influence of the peer group and friends, * other factors which can be related to achievement in mathematics. An empirical investigation was undertaken by means of a self developed attitude scale to determine to which extent attitude towards mathematics can influence achievement in this subject. I.Q. counts and percentages were available from report cards. The most important findings from this study were that attitude influences mathematical achievement to a large extent. Further findings proved that attitudes towards mathematics are influenced largely by the student's previous mathematical achievements, as well as the gender group to which the learner belongs. These findings underline the important role of the teacher, as well as the supportive role of the parents in creating a positive attitude towards Mathematics. The achievement of the learner can be improved by motivation and support. This will result in a more positive attitude towards mathematics and will consequently widen the career choices of the learner. / Thesis (MEd (Voorligting))--PU vir CHO, 1996

The purpose of this study was to determine: * what the influence of attitude is on the mathematical achievement of the standerd 8 pupil, * which factors contribute mainly to the attitude of the standard 8 pupil towards mathematics. The literature study defined the concept "attitude" as widely as possible. The relationship between attitude and academic achievement was discussed and special reference was given to mathematics achievement. In the literature study factors which can influence mathematical achievement were also discussed. Special reference was given to: * cognitive and non-cognitive factors, * factors referring to the parents, * factors referring to the school situation, * the influence of the peer group and friends, * other factors which can be related to achievement in mathematics. An empirical investigation was undertaken by means of a self developed attitude scale to determine to which extent attitude towards mathematics can influence achievement in this subject. I.Q. counts and percentages were available from report cards. The most important findings from this study were that attitude influences mathematical achievement to a large extent. Further findings proved that attitudes towards mathematics are influenced largely by the student's previous mathematical achievements, as well as the gender group to which the learner belongs. These findings underline the important role of the teacher, as well as the supportive role of the parents in creating a positive attitude towards Mathematics. The achievement of the learner can be improved by motivation and support. This will result in a more positive attitude towards mathematics and will consequently widen the career choices of the learner. / Thesis (MEd (Voorligting))--PU vir CHO, 1996

Surface-Enhanced Raman Scattering (SERS) has the potential to be a rapid disease diagnostic platform. SERS is a well-known ultrasensitive, label-free method for the detection and identification of molecules at low concentrations. The Raman cross-sections are primarily enhanced by plasmonic effects for molecules close to (< 5 nm) the surface of nanostructured metal substrates. Due to the unique Raman vibration features that provide molecular signatures, we have shown that SERS can provide a rapid (< one hour), label-free, sensitive and specific diagnosis for a number of diseases. This work demonstrates the capability of SERS to be an effective optical diagnostic approach, in particular, for bacterial infectious diseases such as urinary tract infections (UTI) and sexually transmitted diseases (STD), and cancer cell identification. More specifically, this work demonstrates the ability of SERS to distinguish different vegetative bacterial cells with species and strain specificity based on their intrinsic SERS molecular signatures. With the exception of C. trachomatis - the causative agent of chlamydia - whose SERS molecular signatures are found to be aggregated proteins on the cell membrane, all bacterial SERS molecular signatures are due to purine molecules resulting from nucleic acid metabolism as part of the rapid onset of the starvation response of these pathogens. The differences in relative contribution of different purine metabolites for each bacterium gives rise to the SERS strain and species specificity. The ability of SERS to distinguish cancer and normal cells grown in vitro based on changes of SERS spectral feature as a function of time after sample processing is also demonstrated. Furthermore, the difference of spectral features on the gold and silver SERS substrate of the same bacteria can be used as additional attribute for identification. This work demonstrate the potential of SERS platform to provide antibiotic-specific diagnostics in clinical settings within one hour when combined with a portable Raman microscopy instrument, an effective enrichment procedure, multivariate data analysis and an expendable SERS reference library with drug-susceptibility profile for each bacterial strain determined a priori, as well as the ability of SERS platform as a powerful bioanalytical probe for learning about near cell membrane biochemical processes.