Análise potenciométrica de redissolução com ultramicroeletrodos: fundamentos e aplicações na determinação de metais traços

The Potentiometric Stripping Analysis (PSA) is described with emphasis on ultramicroelectrode applications with a laboratory developed computer based instrumentation. The technique potentialities as compared with the voltammetric approach are pointed out based on the current literature. Some results of trace metals analysis including zinc, cadmium, lead and copper in vinegar and canned food samples are presented. The mainly advantage found in our laboratory was the technique capability to analyse natural samples with minimum matrix interference and the low level of noise found in our determinations.

Model-based objects recognition in industrial environments for autonomous vehicles control

Behavior-based navigation of autonomous vehicles requires the recognition of the navigable areas and the potential obstacles. In this paper we describe a model-based objects recognition system which is part of an image interpretation system intended to assist the navigation of autonomous vehicles that operate in industrial environments. The recognition system integrates color, shape and texture information together with the location of the vanishing point. The recognition process starts from some prior scene knowledge, that is, a generic model of the expected scene and the potential objects. The recognition system constitutes an approach where different low-level vision techniques extract a multitude of image descriptors which are then analyzed using a rule-based reasoning system to interpret the image content. This system has been implemented using a rule-based cooperative expert system

Model-based objects recognition in man-made environments

We describe a model-based objects recognition system which is part of an image interpretation system intended to assist autonomous vehicles navigation. The system is intended to operate in man-made environments. Behavior-based navigation of autonomous vehicles involves the recognition of navigable areas and the potential obstacles. The recognition system integrates color, shape and texture information together with the location of the vanishing point. The recognition process starts from some prior scene knowledge, that is, a generic model of the expected scene and the potential objects. The recognition system constitutes an approach where different low-level vision techniques extract a multitude of image descriptors which are then analyzed using a rule-based reasoning system to interpret the image content. This system has been implemented using CEES, the C++ embedded expert system shell developed in the Systems Engineering and Automatic Control Laboratory (University of Girona) as a specific rule-based problem solving tool. It has been especially conceived for supporting cooperative expert systems, and uses the object oriented programming paradigm

Tapahtumien tutkinnan systematisointi Loviisan voimalaitoksella

Tämä diplomityö käsittelee tapahtumien tutkinnan systematisointia Loviisan voimalaitoksella. Nykyisin Loviisan voimalaitoksella tutkitaan tapahtumia usealla tavalla eikä raporttien tuloksia pystytä täysin hyödyntämään. Diplomityössä käydään läpi erilaisia tapahtumien tutkintamenetelmiä sekä tutustutaan perussyyanalyysimenetelmiin. Matalan tason tapahtumien tutkintaan kehitettiin kysymyslista, jolla saadaan helposti selville tapahtumien ongelma-alueet. Kysymyslista mahdollisti myös tapahtumien laaja-alaisen luokittelun, jonka avulla tunnistetaan eri tapahtumien kautta ilmenneitä yhteisiä ongelma-alueita. Tapahtumien tutkintaan liittyy myös riskien arviointi. Tässä diplomityössä kehitettiin riskimatriisi tapahtuman vakavuuden ja jatkoselvitystarpeen arvioinnin avuksi. Perussyyanalyysimenetelmistä AcciMap-menetelmä osoittautui käyttökelpoiseksi ja sitä suositellaan kokeiltavaksi seuraavan inhimilliseen toimintaan liittyvän perussyyanalyysin yhteydessä.

Disseny de cel·les digitals paramètriques per a electrònica impresa

L’objectiu d’aquest treball és el disseny i la implementació d’un conjunt de cel·les definides de forma paramètrica, i orientades a l’àmbit tecnològic emergent de l’electrònica impresa. L’ús de cel·les paramètriques en aquest entorn tecnològic poc madur, ha de permetre que els dissenys s’adaptin als canvis de regles de disseny de les tecnologies en aquest cas per estils de disseny PMOS.

A graduação em química: um novo químico para uma nova era

The discussions sponsored by the Brazilian Chemical Society, over the past five years, intending to produce a chemistry agenda with perspectives and needs for the next decade for the country, have involved the national chemistry community and several related sectors of Brazilian society. Chemistry education has been the theme throughout these discussions. It is known that the low level of basic and secondary education and the recent increase in high school courses and institutions adversely affect the quality of undergraduate teaching. The recent national "Curriculum Guidelines" for Chemistry Courses, through their flexible approach, encourage the integral, interdisciplinary (non compartmentalized) and critical-reflexive training of professionals as citizens and as entrepreneurs. However, deficiencies are still recognized. The system of undergraduate course evaluation has identified the most fragile modalities of the courses and other indicators. Also, it has been verified that the Brazilian chemistry industry absorbs only minimally the highly qualified professionals, which is attributed to the fact that the Federal Council of Chemistry is vertically organized and does not recognize the graduate degrees as professional qualifications. In conclusion, the importance of the effective implantation of the national curriculum guidelines is apparent, among other aspects, highlighting courses whose didactical and pedagogical projects may offer a solid formation in Chemistry. However, at the same time the guidelines are comprehensive and general enough to enable the chemistry professionals to develop varied skills.

The materiality of the immaterial. Services sectors and CO2 emissions in Uruguay

This paper analyzes the carbon dioxide emissions of the services sectors subsystem of Uruguay in 2004. Services, with the exception of transport, are often considered intangible because of their low level of direct emissions. However, the provision of services requires inputs produced by other sectors, including several highly materialintensive sectors. Through input–output analysis we investigate the relationship between the services subsystem and the rest of the economy as regards carbon dioxide emissions. This approach allows us to study the importance of the set of services branches as a unit in the economic structure as well as to analyze in detail the relationship between the branches. The results depict that services’ direct emissions are the main component, as a consequence of transport-related sectors. However, the pollution that the services subsystem makes the rest of the economy produce is very significant, and it is almost all explained by non-transport-related sectors. This analysis is useful for determining the sectors in which mitigation policies are more effective, and whether they would be better tackled through technical improvements and better practices or through demand policies.

Physical activity in adolescence - with special reference to cardiovascular health

Liikunta ja sydän- ja verisuoniterveys nuorilla Aikuisiällä ilmenevien sydän- ja verisuonisairauksien kehitys alkaa lapsuudessa. Vähäinen liikunta lisää vaaraa sairastua sydän- ja verisuonisairauksiin sekä vaikuttaa haitallisesti näiden sairauksien riskitekijöihin läpi elämän. Tämän tutkimuksen tavoitteena oli tutkia nuorten liikuntaa ja sen yhteyttä sydän- ja verisuoniterveyteen. Sydän- ja verisuoniterveyttä tutkittiin riskitekijöiden sekä valtimon laajentumiskyvyn avulla. Tutkittavat koostuivat nuorista, jotka osallistuivat pitkäaikaisen sepelvaltimotaudin ehkäisytutkimuksen (STRIP) 13-vuotistutkimuskäynnille ja jotka raportoivat vapaa-ajan liikuntatottumuksensa (n=560). Liikunnan lisäksi nuorten pituus, paino, verenpaine ja olkavaltimon laajentumiskyky mitattiin sekä analysoitiin laboratorionäytteitä (otettiin verinäyte) ja selvitettiin ruoankäyttöä. Vähäinen vapaa-ajan liikunta oli yleistä etenkin tytöillä. Vapaa-ajallaan vähän liikkuvat pojat viettivät enemmän aikaa televisio- ja tietokoneruudun ääressä kuin vapaa-ajallaan paljon liikkuvat pojat. Äidin, toisin kuin isän, vapaa-ajan liikunta ja paino olivat yhteydessä lapsen vapaa-ajan liikuntaan. Vähän liikkuvat tytöt olivat olleet jo kahden vuoden iästä saakka useammin ylipainoisia kuin runsaammin liikkuvat ikätoverinsa. Sydän- ja verisuonisairauksien riskitekijöiden kasautuminen oli tavallisempaa vähän kuin paljon liikkuvilla nuorilla. Vähän liikkuvilla pojilla oli lisäksi huonompi olkavaltimon laajentumiskyky kuin paljon liikkuvilla pojilla. Tämä on tärkeä löydös, koska valtimon laajentumiskyky kuvannee sydän- ja verisuoniterveyttä jo ennen rakenteellisten muutosten ilmaantumista. Useat nuoret, etenkin tytöt, liikkuivat vähän vapaa-ajallaan. Vähäisellä vapaa-ajan liikunnalla oli haitallinen yhteys sydän- ja verisuonisairauksien riskitekijöihin sekä valtimon laajentumiskykyyn. Nuorten kannustaminen liikunnalliseen elämäntapaan on erittäin tärkeää sydän- ja verisuoniterveyden edistämiseksi sekä nuoren että kansanterveyden kannalta.

Salmonella enterica– Mechanisms of fluoroquinolone and macrolide resistance

Salmonella enterica – Fluorokinoloni- ja makrolidiresistenssimekanisimit Vakavia salmonellainfektioita on pitkään hoidettu fluorokinoloniantibiooteilla, kuten siprofloksasiinilla. Fluorokinolonien runsas käyttö niin ihmisillä kuin eläimilläkin on kuitenkin johtanut fluorokinoloniresistenttien salmonellakantojen lisääntymiseen. Vuoteen 2002 asti kaikki matalan tason fluorokinoloniresistenssiä ilmentävät salmonellakannat olivat resistenttejä nalidiksiinihapolle, joka on vanha ensimmäisen polven kinoloniantibiootti jota ei enää käytetä infektioiden hoidossa. Vuonna 2003 havaitsimme aivan uudentyyppisen resistenssifenotyypin salmonelloissa. Kaikki uuden fenotyypin kannat osoittivat matalaa fluorokinoloniresistenssiä (MIC ≥0.125 mg/L), mutta useat kannat olivat yllättäen aikaisempaa herkempiä nalidiksiinihapolle (MIC ≤32 mg/L). Ilmiöllä on suuri merkitys salmonellan antibioottiherkkyyksien määrittämisessä, sillä jos kanta on ollut nalidiksiinihapolle herkkä, sitä on pidetty herkkänä myös fluorokinoloneille. Väitöskirjatyössä määritettiin vuosina 2003–2007 Suomessa kerättyjen kotimaisten ja ulkomaalaisten S. enterica -kantojen fluorokinoloniresistenssiä sekä tutkittiin uuden salmonellafenotyypin epidemiologiaa ja resistenssimekanismeja. Lisäksi tutkittiin salmonellan hoidossa mahdollisesti käyttökelpoisen makrolidiantibioottijohdannaisen, atsitromysiinin tehoa salmonelloihin ja erityisesti matalaa fluorokinoloniresistenssiä ilmentäviin kantoihin. Tutkimuksessa havaittiin, että matalaa fluorokinoloniresistenssiä osoittavien salmonellakantojen määrä vähenee. Lasku oli voimakkainta Kaakkois-Aasiasta tuoduissa kannoissa. Uusi resistenssifenotyyppi on plasmidivälitteinen ja qnr-geenit olivat ainoa plasmidivälitteinen kinoloniresistenssimekanismi, joka kannoista löydettiin. Myöskään kromosomaalisten gyrA, gyrB ja parE -geenien QRDR-alueelta ei löydetty fluorokinoloniresistenssiä aiheuttavia mutaatioita. Transformaatiolla osoitettiin qnr-plasmidien olevan siirtyviä ja uusi resistenssifenotyyppi saatiin ilmennettyä myös herkässä vastaanottajakannassa. Nämä tulokset osoittavat, että vaikka S. enterican qnr-fenotyyppi on toistaiseksi levinnyt pääasiassa Kaakkois-Aasiaan, se siirtyy helposti bakteerista toiseen ja tulee todennäköisesti aiheuttamaan hoito-ongelmia myös muualla maailmassa. Uudentyyppinen qnr-fenotyyppi voi olla vaikea havaita perinteisellä herkkyysmäärityksellä. Siksi laboratorioissa tulisi aina määrittää sekä siprofloksasiiniettä nalidiksiinihappoherkkyydet. Atsitromysiinin osoitettiin olevan herkkyysmääritysten mukaan tehokas salmonelloja kohtaan mukaanlukien matala-asteista fluorokinoloniresistenssiä ilmentävät bakteerikannat.

Counselling on limited preoperative fasting in paediatric ambulatory tonsillectomy

Rajoitetun preoperatiivisen paaston ohjaus lasten päiväkirurgisessa nielurisaleikkauksessa Tutkimuksen tarkoituksena oli selvittää, onko sairaanhoitajan toteuttama, vanhempien interaktiivinen preoperatiivinen ohjaus lapsen rajoitettuun preoperatiiviseen paastoon ja aktiiviseen nesteyttämiseen turvallista, kuinka vanhemmat omaksuvat kyseistä tietoa ja edistääkö se turvallisesti lapsen postoperatiivista toipumista päiväkirurgisen nielurisaleikkauksen jälkeen. Aineisto koostui sadastakuudestatoista perheestä, joiden lapsi, iältään 4 – 10 vuotta, oli kutsuttu päiväkirurgiseen nielurisaleikkaukseen. Koeryhmä (n= 58) ohjattiin interaktiivisesti lapsen preoperatiiviseen paastoon ja aktiiviseen preoperatiiviseen nesteyttämiseen. Lapsen suositellut preoperatiiviset paastoajat olivat: 4t syömättä ja 2t juomatta. Leikkauspäivän aamuna vanhemmat rohkaisivat lapsia juomaan annokset kirkkaita nesteitä kahteen otteeseen; jälkimmäinen annos 2t ennen leikkausta. Kontrolliryhmä (n= 58) sai preoperatiivisen ohjauksen kirjallisena ilman interaktiivista ohjausta; paastoajat olivat samat kuin koeryhmässä: 4t syömättä ja 2t juomatta. Vanhempien tiedontasoa lapsen leikkaukseen liittyvästä paastosta mitattiin tietotestillä, joka sisälsi myös preoperatiivista tiedontarvetta ja ahdistusta mittaavan mittarin (The Amsterdam Preoperative Anxiety and Information scale, APAIS). Mittaukset suoritettiin ennen preoperatiivista ohjausta tai kirjallisten ohjeiden lähettämistä sekä lapsen leikkausta seuraavana päivänä. Lapsen leikkauksen jälkeen vanhemmat arvioivat myös heille välitetyn informaation tasoa. Lapsen postoperatiivista kipua, pahoinvointia, janoa ja nälkää lapset itse arvioivat VAS- asteikolla (10cm), ja vanhemmat ja sairaanhoitajat numeerisella 0 – 10 asteikolla. Mittaukset suoritettiin 2t, 4t, 8t, ja 24t lapsen leikkauksen jälkeen. Vanhemmat pitivät päiväkirjaa lapsen ravinnosta ja kipulääkityksestä. Aineisto analysoitiin sekä tilastollisesti että sisällön analyysilla. Vanhempien tiedontaso lapsen leikkauksen jälkeen oli molemmissa ryhmissä merkitsevästi parantunut, mutta kontrolliryhmän vanhempien ahdistus ei ollut helpottanut verrattuna heidän ahdistukseensa ennen lapsen leikkausta. Mitä korkeammat pisteet vanhemmat saivat tietotestistä lapsen leikkauksen jälkeen sitä vähemmän he tunsivat tiedontarvetta ja ahdistusta. Merkitsevästi alhaisemmat pisteet tietotestistä oli vanhemmilla, joilla oli alempi peruskoulutus. Kontrolliryhmän lapset paastosivat preoperatiivisesti merkitsevästi pitempään kuin koeryhmän lapset. Perioperatiivisesti lapset paastosivat kiinteästä ruuasta yhtä kauan, mutta nesteistä kontrolliryhmä merkitsevästi pitempään. Postoperatiivisen toipumisen alussa koeryhmän lapset olivat merkitsevästi kivuttomampia. Molemmissa ryhmissä lapset olivat kipeimpiä kahdeksan tuntia leikkauksesta ja pahoinvointisimpia neljä tuntia leikkauksesta. Ensimmäisen kahdeksan tunnin aikana leikkauksen jälkeen lapset eivät olleet janoisia tai nälkäisiä, mutta VAS- arvot koeryhmässä jäivät alhaisemmalle tasolle kuin kontrolliryhmässä 24 postoperatiivisen tunnin ajan. Leikkausta seuraavana aamuna kontrolliryhmän lapset olivat merkitsevästi janoisempia ja nälkäisempiä kuin interventioryhmän lapset. Sairaanhoitajan toteuttama vanhempien interaktiivinen preoperatiivinen ohjaus lapsen rajoitettuun preoperatiiviseen paastoon lisää vanhempien tiedontasoa ja vähentää preoperatiivista tiedontarvettaan ja ahdistusta, ja turvallisesti parantaa lapsen kokemusta leikkausprosessin ja postoperatiivisen toipumisen aikana nielurisaleikkauksen jälkeen. Kaikkien leikkaukseen tulevien lasten nesteyttäminen kaksi tuntia ennen päivän ensimmäistä leikkausta voi olla ratkaisu lasten kohtuuttomien perioperatiivisten paastoaikojen estämiseksi. Aina ei kuitenkaan ole mahdollisuuksia vanhempien henkilökohtaiseen kohtaamiseen, mikä haastaa hoitotieteellisen tutkimuksen kartoittamaan muita mahdollisuuksia vanhempien interaktiiviseen ohjaukseen.

Genetic variation among pathogens causing "Helminthosporium" diseases of rice, maize and wheat

Twenty isolates of four fungal species, agents of "Helminthosporium" diseases in cereals, were collected from different regions: nine Bipolarisoryzae isolated from rice (Oryza sativa), seven B.sorokiniana from wheat (Triticum aestivum), two B. maydis, and two Exserohilumturcicum from maize (Zea mays). The strains were compared by PCR-RFLP and RAPD analysis. Size polymorphism among the isolates in the ITS region comprising the 5.8 S rDNA indicated genetic differences among the isolates, while a UPGMA phenogram constructed after the digestion of this region with restriction enzymes showed inter- and intra-specific polymorphism. The RAPD profiles indicated an expressive level of polymorphism among different species, compared with a low level of polymorphism among isolates of the same species. A UPGMA phenogram grouped the isolates according to the species and their host plant. RAPD profiles did not reveal polymorphism that directly correlated climatic factors with geographic source of the isolates of B. sorokiniana, and B. oryzae. Teleomorphic species revealed high similarity with their correspondent anamorphs.

Multilevel converter modulation: implementation and analysis

Multilevel converters provide an attractive solution to bring the benefits of speed-controlled rotational movement to high-power applications. Therefore, multilevel inverters have attracted wide interest in both the academic community and in the industry for the past two decades. In this doctoral thesis, modulation methods suitable especially for series connected H-bridge multilevel inverters are discussed. A concept of duty cycle modulation is presented and its modification is proposed. These methods are compared with other well-known modulation schemes, such as space-vector pulse width modulation and carrier-based modulation schemes. The advantage of the modified duty-cycle modulation is its algorithmic simplicity. A similar mathematical formulation for the original duty cycle modulation is proposed. The modified duty cycle modulation is shown to produce well-formed phase-to-neutral voltages that have lower total harmonic distortion than the space-vector pulse width modulation and the duty cycle modulation. The space-vector-based solution and the duty cycle modulation, on the other hand, result in a better-quality line-to-line voltage and current waveform. The voltage of the DC links in the modules of the series-connected H-bridge inverter are shown to fluctuate while they are under load. The fluctuation causes inaccuracies in the voltage production, which may result in a failure of the flux estimator in the controller. An extension for upper-level modulation schemes, which changes the switching instants of the inverter so that the output voltage meets the reference voltage accurately regardless of the DC link voltages, is proposed. The method is shown to reduce the error to a very low level when a sufficient switching frequency is used. An appropriate way to organize the switching instants of the multilevel inverter is to make only one-level steps at a time. This causes restrictions on the dynamical features of the modulation schemes. The produced voltage vector cannot be rotated several tens of degrees in a single switching period without violating the above-mentioned one-level-step rule. The dynamical capabilities of multilevel inverters are analyzed in this doctoral thesis, and it is shown that the multilevel inverters are capable of operating even in dynamically demanding metal industry applications. In addition to the discussion on modulation schemes, an overvoltage in multilevel converter drives caused by cable reflection is addressed. The voltage reflection phenomenon in drives with long feeder cables causes premature insulation deterioration and also affects the commonmode voltage, which is one of the main reasons for bearing currents. Bearing currents, on the other hand, cause fluting in the bearings, which results in premature bearing failure. The reflection phenomenon is traditionally prevented by filtering, but in this thesis, a modulationbased filterless method to mitigate the overvoltage in multilevel drives is proposed. Moreover, the mitigation method can be implemented as an extension for upper-level modulation schemes. The method exploits the oscillations caused by two consecutive voltage edges so that the sum of the oscillations results in a mitigated peak of the overvoltage. The applicability of the method is verified by simulations together with experiments with a full-scale prototype.

Understanding the Racial Nature of Police and Immigrant Relations In Finland. The Case of Africans in Turku

The focus of this study is to examine the role of police and immigrants’ relations, as less is known about this process in the country. The studies were approached in two different ways. Firstly, an attempt was made to examine how immigrants view their encounters with the police. Secondly, the studies explored how aware the police are of immigrants’ experiences in their various encounters and interactions on the street level. An ancillary aim of the studies is to clarify, analyse and discuss how prejudice and stereotypes can be tackled, thereby contributing to the general debate about racism and discrimination for better ethnic relations in the country. The data in which this analysis was based is on a group of adults (n=88) from the total of 120 Africans questioned for the entire study (n=45) police cadets and (n=6) serving police officers from Turku. The present thesis is a compilation of five articles. A summary of each article findings follows, as the same data was used in all five studies. In the first study, a theoretical model was developed to examine the perceived knowledge of bias by immigrants resulting from race, culture and belief. This was also an attempt to explore whether this knowledge was predetermined in my attempt to classify and discuss as well as analyse the factors that may be influencing immigrants’ allegations of unfair treatment by the police in Turku. The main finding shows that in the first paper there was ignorance and naivety on the part of the police in their attitudes towards the African immigrant’s prior experiences with the police, and this may probably have resulted from stereotypes or their lack of experience as well as prior training with immigrants where these kinds of experience are rampant in the country (Egharevba, 2003 and 2004a). In exploring what leads to stereotypes, a working definition is the assumption that is prevalent among some segments of the population, including the police, that Finland is a homogenous country by employing certain conducts and behaviour towards ethnic and immigrant groups in the country. This to my understanding is stereotype. Historically this was true, but today the social topography of the country is changing and becoming even more complex. It is true that, on linguistic grounds, the country is multilingual, as there are a few recognised national minority languages (Swedish, Sami and Russian) as well as a number of immigrant languages including English. Apparently it is vital for the police to have a line of communication open when addressing the problem associated with immigrants in the country. The second paper moved a step further by examining African immigrants’ understanding of human rights as well as what human rights violation means or entails in their views as a result of their experiences with the police, both in Finland and in their country of origin. This approach became essential during the course of the study, especially when the participants were completing the questionnaire (N=88), where volunteers were solicited for a later date for an in-depth interview with the author. Many of the respondents came from countries where human rights are not well protected and seldom discussed publicly, therefore understanding their views on the subject can help to explain why some of the immigrants are sceptical about coming forward to report cases of batteries and assaults to the police, or even their experiences of being monitored in shopping malls in their new home and the reason behind their low level of trust in public authorities in Finland. The study showed that knowledge of human rights is notably low among some of the participants. The study also found that female respondents were less aware of human rights when compared with their male counterparts. This has resulted in some of the male participants focussing more on their traditional ways of thinking by not realising that they are in a new country where there is equality in sexes and lack of respect on gender terms is not condoned. The third paper focussed on the respondents’ experiences with the police in Turku and tried to explore police attitudes towards African immigrant clients, in addition to the role stereotype plays in police views of different cultures and how these views have impacted on immigrants’ views of discriminatory policing in Turku. The data is the same throughout the entire studies (n=88), except that some few participants were interviewed for the third paper thirty-five persons. The results showed that there is some bias in mass-media reports on the immigrants’ issues, due to selective portrayal of biases without much investigation being carried out before jumping to conclusions, especially when the issues at stake involve an immigrant (Egharevba, 2005a; Egharevba, 2004a and 2004b). In this vein, there was an allegation that the police are even biased while investigating cases of theft, especially if the stolen property is owned by an immigrant (Egharevba, 2006a, Egharevba, 2006b). One vital observation from the respondents’ various comments was that race has meaning in their encounters and interaction with the police in the country. This result led the author to conclude that the relation between the police and immigrants is still a challenge, as there is rampant fear and distrust towards the police by some segments of the participating respondents in the study. In the fourth paper the focus was on examining the respondents’ view of the police, with special emphasis on race and culture as well as the respondents’ perspective on police behaviour in Turku. This is because race, as it was relayed to me in the study, is a significant predictor of police perception (Egharevba, 2005a; Egharevba and Hannikianen, 2005). It is a known scientific fact that inter-group racial attitudes are the representation of group competition and perceived threat to power and status (Group-position theory). According to Blumer (1958) a sense of group threat is an essential element for the emergence of racial prejudice. Consequently, it was essential that we explored the existing relationship between the respondents and the police in order to have an understanding of this concept. The result indicates some local and international contextual issues and assumptions that were of importance tackling prejudice and discrimination as it exists within the police in the country. Moreover, we have to also remember that, for years, many of these African immigrants have been on the receiving end of unjust law enforcement in their various countries of origin, which has resulted in many of them feeling inferior and distrustful of the police even in their own country of origin. While discussing the issues of cultural difference and how it affects policing, we must also keep in mind the socio-cultural background of the participants, their level of language proficiency and educational background. The research data analysed in this study also confirmed the difficulties associated with cultural misunderstandings in interpreting issues and how these misunderstandings have affected police and immigrant relations in Finland. Finally, the fifth paper focussed on cadets’ attitudes towards African immigrants as well as serving police officers’ interaction with African clients. Secondly, the police level of awareness of African immigrants’ distrustfulness of their profession was unclear. For this reason, my questions in this fifth study examined the experiences and attitudes of police cadets and serving police officers as well as those of African immigrants in understanding how to improve this relationship in the country. The data was based on (n=88) immigrant participants, (n=45) police cadets and 6 serving police officers from the Turku police department. The result suggests that there is distrust of the police in the respondents’ interaction; this tends to have galvanised a heightened tension resulting from the lack of language proficiency (Egharevba and White, 2007; Egharevba and Hannikainen, 2005, and Egharevba, 2006b) The result also shows that the allegation of immigrants as being belittled by the police stems from the misconceptions of both parties as well as the notion of stop and search by the police in Turku. All these factors were observed to have contributed to the alleged police evasiveness and the lack of regular contact between the respondents and the police in their dealings. In other words, the police have only had job-related contact with many of the participants in the present study. The results also demonstrated the complexities caused by the low level of education among some of the African immigrants in their understanding about the Finnish culture, norms and values in the country. Thus, the framework constructed in these studies embodies diversity in national culture as well as the need for a further research study with a greater number of respondents (both from the police and immigrant/majority groups), in order to explore the different role cultures play in immigrant and majority citizens’ understanding of police work.

Bag-of-Features Approach to Unsupervised Visual Object Categorisation

The large and growing number of digital images is making manual image search laborious. Only a fraction of the images contain metadata that can be used to search for a particular type of image. Thus, the main research question of this thesis is whether it is possible to learn visual object categories directly from images. Computers process images as long lists of pixels that do not have a clear connection to high-level semantics which could be used in the image search. There are various methods introduced in the literature to extract low-level image features and also approaches to connect these low-level features with high-level semantics. One of these approaches is called Bag-of-Features which is studied in the thesis. In the Bag-of-Features approach, the images are described using a visual codebook. The codebook is built from the descriptions of the image patches using clustering. The images are described by matching descriptions of image patches with the visual codebook and computing the number of matches for each code. In this thesis, unsupervised visual object categorisation using the Bag-of-Features approach is studied. The goal is to find groups of similar images, e.g., images that contain an object from the same category. The standard Bag-of-Features approach is improved by using spatial information and visual saliency. It was found that the performance of the visual object categorisation can be improved by using spatial information of local features to verify the matches. However, this process is computationally heavy, and thus, the number of images must be limited in the spatial matching, for example, by using the Bag-of-Features method as in this study. Different approaches for saliency detection are studied and a new method based on the Hessian-Affine local feature detector is proposed. The new method achieves comparable results with current state-of-the-art. The visual object categorisation performance was improved by using foreground segmentation based on saliency information, especially when the background could be considered as clutter.

In vivo imaging of vascular adhesion protein 1 - preclinical studies with positron emission tomography

The golden standard in nuclear medicine imaging of inflammation is the use of radiolabeled leukocytes. Although their diagnostic accuracy is good, the preparation of the leukocytes is both laborious and potentially hazardous for laboratory personnel. Molecules involved in leukocyte migration could serve as targets for the development of inflammation imaging agents. An excellent target would be a molecule that is absent or expressed at low level in normal tissues, but is induced or up-regulated at the site of inflammation. Vascular adhesion protein-1 (VAP-1) is a very promising target for in vivo imaging, since it is translocated to the endothelial cell surface when inflammation occurs. VAP-1 functions as an endothelial adhesion molecule that participates in leukocyte recruitment to inflamed tissues. Besides being an adhesion molecule, VAP-1 also has enzymatic activity. In this thesis, the targeting of VAP-1 was studied by using Gallium-68 (68Ga) labeled peptides and an Iodine-124 (124I) labeled antibody. The peptides were designed based on molecular modelling and phage display library searches. The new imaging agents were preclinically tested in vitro, as well as in vivo in animal models. The most promising imaging agent appeared to be a peptide belonging to the VAP-1 leukocyte ligand, Siglec-9 peptide. The 68Ga-labeled Siglec-9 peptide was able to detect VAP-1 positive vasculature in rodent models of sterile skin inflammation and melanoma by positron emission tomography. In addition to peptides, the 124I-labeled antibody showed VAP-1 specific binding both in vitro and in vivo. However, the estimated human radiation dose was rather high, and thus further preclinical studies in disease models are needed to clarify the value of this imaging agent. Detection of VAP-1 on endothelium was demonstrated in these studies and this imaging approach could be used in the diagnosis of inflammatory conditions as well as melanoma. These studies provide a proof-of-concept for PET imaging of VAP-1 and further studies are warranted.