887 resultados para Criminal investigations
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Tutkielman tavoitteena on oikeudellisten lähteiden systematisoinnilla tuottaa johdonmukainen kuvaus poliisin, rajavartiomiehen sekä ammattisotilaan virkavelvollisuuksista, oikeudellisesta vastuusta ja virkarikosten rangaistavuudesta. Päähuomio kohdistuu virkamiehen määräaikaiseen virantoimituksesta erottamiseen. Oikeudellisella argumentaatiolla pyritään esittämään lainmukainen ja hyväksyttävä tulkintakannanotto siihen, miten kyseistä säädöstä tulisi tulkita. Tutkimusmetodi työssä on oikeusdogmatiikka. Ensisijaisena aineistona tutkielmassa on voimassa oleva lainsäädäntö valmisteluaineistoineen. Toissijaisina lähteinä käytetään kirjallisuutta, viranomaisten kurinpitopäätöksiä ja haastatteluja. Määräaikainen erottaminen voidaan määrätä virkamiehelle, joka toimii vastoin virkavelvollisuuksiaan tai laiminlyö niitä. Säädös on tulkittavissa laajentavasti siten, että myös muut kuin selkeästi viranomaisen valvontavastuulle kuuluvat teot voidaan katsoa virkatehtävien vastaiseksi. Erityisen käyttäytymisvelvoitteen johdosta menettely on rangaistavaa myös vapaa-ajalla. Määräaikainen erottaminen sijoittuu rangaistusasteikossa varoituksen ja irtisanomisen väliin. Rangaistus ei edellytä erityisen painavia perusteita, joita vaaditaan virkamiehen irtisanomiseen. Uuden säädöksen myötä irtisanomisten määrä on vähentynyt Rajavartiolaitoksessa. Säädöksestä on muotoutunut kurinpidollinen lisärangaistus, joka on määrätty virkamiehelle hallinnollisella päätöksellä yleensä rikostuomion jälkeen. Säädös on kuitenkin tarkoitettu ja se mahdollistaa myös puuttumisen varsinaisten virkatehtävien laiminlyönteihin. Lainsäädännön selkeyttämiseksi määräaikaisen erottamisen säädös tulisi poistaa eri viranomaisten erityislainsäädännöstä ja liittää suoraan virkamieslakiin. Säädöksen soveltaminen tulisi ulottaa koskemaan myös muita virkamiehiä, jotka palvelevat kyseisissä viranomaisissa. Tutkimuksen kohteena oleva virkamiesryhmä alistuu virkamiesoikeudessa blankkorangaistusuhan alle. Virkamiehen on vaikea hahmottaa kaikkea rangaistavaa toimintaa, ja virantoimittamisvelvollisuus on usein täsmentymätön ja tulkinnanvarainen. Kokonaisharkinnassa korostuvat myös muut kuin oikeudelliset lähteet (esimerkiksi moraalikäsitykset, etiikka, ohjeet, virkamiehen elämäntilanne). Sotilaiden ja poliisin oikeudenhoito poikkeaa monilta osin muiden virkamiesten oikeudenhoitomenettelystä. Rajavartiolaitoksessa sotilasoikeudenhoidon määräykset ja ohjeet ovat selkeästi puutteelliset. Rajavartiolaitoksen tehtäväkentän ja toimivaltuudet huomioiden tulisi kurinpito- ja virkarikosten tutkinnoissa lähentyä poliisin mallia sekä hyödyntää rikostorjuntahenkilöstön ammattitaitoa oman henkilökunnan esitutkinnoissa. Erityisen turvallisuusviranomaisten virkarikoksiin erikoistuneen tutkintaorganisaation perustaminen voisi tehostaa ja parantaa esitutkintojen tasoa sekä lisätä oikeusvarmuutta.
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The course of reaction between cerium(III) nitrate and different sodium tungstates (Na2WO4, Na10W12O41 and Na6W12O39) has been followed by means of pH and conductometric titrations between the reactants at different pH levels, in aqueous and alcoholic media, with each of the reagents alternatively used as titrant. The electrometric experiments provide definite evidence of the formation of normal-Ce2O3.3WO3 and para- 5Ce2O3.36WO3 tungstates of cerium in the vicinity of pH 6.2 and 5.3. The formation of normal tungstate is almost quantitative and the pH titrations offer a simple means for determination of cerium(III) or tungstate solutions at suitable concentrations and pH range.
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Colloid chemical behavior of indole dihydropyrimidines in non-aqueous solvent mixture benzene-methanol of varying composition has been investigated by viscometric measurements at 303K± 0.1. The viscosity of the system increases with the increase in concentration. The Trend Change Point (TCP) values have been determined by intersection of two straight lines, which are found to be dependent on the composition of solvent mixtures. The study confirms that the nature of synthesized compounds agglomerate formed below and above 50% benzene concentration is quite different. The viscometric data have been analyzed in terms of Einstein, Vand, Moulik and Jones-Dole equations. These well known equations have been successfully applied to explain the results of viscosity measurements and the viscometric parameters show that the behavior of compound changes in the proximity of 50% benzene concentration.
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Tämä tutkielma käsittelee poptähti Michael Jacksonin tähtikuvaa populaarina myyttinä arkkityyppien näkökulmasta. Tutkimus käsittelee myös tähteyden historiaa ja siirtymää klassisesta Hollywood -tähteydestä postmoderniin tähteyteen. Tutkimus pyrkii selvittämään Jacksonin positiota kulttuurisella tähtikentällä ja sitä, mitä uutta rajatilasankarin, initiaation ja tricksterin arkkityypit voivat kertoa tunnetusta poptähdestä. Tutkimusaineistoksi on valittu Jacksonin Moonwalker –elokuva (1988) ja sen sisällä oleva Smooth Criminal -osio, joka sisältää juonellisen tarinan ja musiikkivideokohtauksen. Smooth Criminal -musiikkikohtaus viittaa kulta-ajan Hollywood -tähden Fred Astairen Band Wagon –musikaalin (1953) Girl Hunt Ballet -musikaalinumeroon. Tutkimuksen kulttuurihistoriallisessa osiossa tuodaan vertailuun Astairen ja Jacksonin erilaiset tähteydet, videoiden narratiivit ja sankaruudet, joita tähdet ilmentävät narratiiveissa. Arkkityyppeihin keskittyvässä osiossa sama Smooth Criminal -narratiivi luetaan uudestaan näiden kolmen arkkityypin kautta, jolloin Jacksonin tähtikuvasta avautuu uusia aspekteja. Tutkimuksen teoreettisen rungon muodostavat sveitsiläisen analyyttisen psykologian perustajan Carl Gustav Jungin teoria arkkityypeistä ja tätä teoriaa soveltava postjungilainen tutkimus. Tutkimuksen kulttuurihistoriallinen puoli pohjaa perinteiseen tähtitutkimukseen ja erityisesti Richard Dyerin sekä Edgar Morinin teoksiin. Käytän postjungilaista elokuva- ja tähtitutkimusta tutkimuksessani, joista tärkeimpiä ovat John Izodin ja Luke Hockleyn teokset. Tutkimuksen perusteella voidaan todeta, että tähteys on kulttuurisidonnaista ja ilmentää omaa aikaansa. Astairen tähteys ja narratiivin sankaruus koostuu muutamista pelkistetyistä aspekteista. Jackson on tähtenä eräänlainen hybridisankari, jossa yhdistyvät monet vastakkaiset merkitykset. Rajatilasankarin, initiaation ja tricksterin arkkityypit ovat kaikki löydettävissä tutkinnan kohteena olevasta narratiivista. Arkkityyppien kautta voi nähdä, että Jacksonin ilmensi tähteydessään myös näitä kaikille ihmisille yhteisiä psyykkisiä sisältöjä, mikä voi osaltaan selittää hänen globaalia suosiotaan.
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The present thesis had two main objectives: The first was to assess how child sexual abuse (CSA) interviews in Finland are conducted through analysing the interviewing techniques applied and the language used by the interviewers, as well as to suggest ways to improve interviews if they were found to have deficiencies. The second main aim was to contribute to the growing research corpus concerning CSA interviews, in particular, by addressing how interviewers follow up information provided by the child, by analysing whether child health care professionals would use childadapted language, and by studying the kind of modifications in the verbal behaviour of interviewers and children that were associated with a) repeated interviews, b) a support person’s presence at the interview, and c) the use of anatomically detailed dolls. Two complementary samples of CSA interviews were analysed. The first one was composed of child interviews with 3-12-year-old children (N = 27) that had been considered problematic by lawyers or other involved professionals (Studies I and IV). The second sample consisted of unselected interviews (N = 43) with children aged 3 to 8 years conducted in a number of hospitals in different parts of the country (Studies II and III). Study I: The verbal interaction between interviewer and child was analysed in a sample of interviews that had been considered to be problematic by involved professionals. Results showed that interviewers used inappropriate questioning techniques, relying on option-posing, specific suggestive and unspecific suggestive questions to a significant extent, these comprising around 50% of all interviewer utterances. The proportion of invitations, which the research community recommends interviewers to rely on, was strikingly low. Invitations and directive utterances were associated with an increase in informative responses by the child in terms of response type, number of new details reported, as well as length of response. The opposite was true for option-posing and suggestive utterances. Longer questions by the interviewer (in number of words) often rendered no reply from the child, whereas shorter questions were followed by descriptive answers. Even after the child had provided an informative answer, interviewers failed to follow up the information in an adequate way and instead continued to rely on focused and leading questions. Study II: Due to the possible bias of the sample analysed in Study I, the most important analyses were rerun with the unselected sample and reported separately. Results were quite similar between the two studies, indicating that the problems observed in Study I, with interviewers relying on option-posing and suggestive questions to a significant extent, are likely to be general and not specific for those interviews. Even if suggestive questions were slightly less and invitations slightly more common in this sample than in the previous study, almost half of the interviewer questions were still optionposing or suggestive, and also in this sample, interviewers failed to follow up information by the child in a facilitating manner. Differentiating between judicial and contextual details showed that while facilitators, invitations, and directive utterances elicited more contextual than judicial details, the opposite was true for specific suggestive utterances. These results might be explained by the reluctance of children to describe sexual details related to the abuse events. Alternatively, they may also be due to children describing incorrect sexual details as a result of suggestive interviewing techniques. Study III: This study examined features of the language used by the interviewers. Interviewer utterances included multiple questions, long statements, complicated grammar and concepts, as well as unclear references to persons and situations. More than a fifth of the interviewer utterances were coded as belonging to at least one of these categories. The results suggest that even professionals who are experienced in interacting with children may have difficulties in using a child-sensitive language, adding to the pool of studies showing similar problems to occur in legal hearings with children conducted by lawyers. As children rarely comment on, or even recognise, their lack of comprehension, the use of a language that is too complex can have detrimental consequences for the outcomes of investigative interviews. Interviewers used different approaches to introduce the topic of abuse. While 15% of the children spontaneously addressed the topic of abuse, probably indicating that they felt confident with the interviewer and the situation, in almost 50% of the cases, the interviewer introduced the topic of abuse in a way that can be considered leading. Interviews were characterised by a lack of structure, apparent in frequent rapid switches of topic by the interviewer. This manner was associated with a decrease in the number of new details provided by the children. Study IV: This study analysed possible changes in the interview dynamics associated with repeated interviewing, the presence of a support person (related to the child), and the use of anatomically detailed (AD) dolls. Repeated interviewing, in combination with suggestive questions, has previously been found to seriously contaminate children’s accounts. In the present material, interviewers used significantly more suggestive utterances in the repeated condition, thus endangering the reliability of the children’s reports. Few studies have investigated the effects of a support person’s presence at the interview. The results of the present study showed that interviewers talked more and children provided less information when a support person was present. Supporting some earlier findings regarding the use of AD dolls, the present results showed that using AD dolls was associated with longer interviewer utterances and shorter, less responsive, and less detailed child responses. Interviewers used up to five times more unspecific suggestive utterances when dolls were used, for instance through repeatedly asking the child to show “what really happened” with the dolls. Conclusion: The results indicate that CSA interviews in Finland are not conducted in a manner that follows best practice as defined by the research community and as stated in a number of guidelines. When comparing these questioning strategies with the recommendations, which have been predominant in the field for more than ten years now, it can be concluded that the interviews analysed were conducted in a manner that undermines the possibility to elicit an uncontaminated and accurate narrative from the children. A particularly worrying finding was the fact that interviewers did not follow up relevant information by the children in an adequate way. A number of clinical implications can be drawn from the results, particularly concerning the need for improvement in the quality of CSA interviews. There is convincing research regarding how to improve CSA interviews, notably through training forensic child interviewers to use a structured interviewing protocol, and providing them with continuous supervision and feedback. Allocating appropriate resources to improve the quality of forensic child interviews is a matter of protecting the rights of all persons involved in CSA investigations, in particular those of the children.
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Med prediktion avses att man skattar det framtida värdet på en observerbar storhet. Kännetecknande för det bayesianska paradigmet är att osäkerhet gällande okända storheter uttrycks i form av sannolikheter. En bayesiansk prediktiv modell är således en sannolikhetsfördelning över de möjliga värden som en observerbar, men ännu inte observerad storhet kan anta. I de artiklar som ingår i avhandlingen utvecklas metoder, vilka bl.a. tillämpas i analys av kromatografiska data i brottsutredningar. Med undantag för den första artikeln, bygger samtliga metoder på bayesiansk prediktiv modellering. I artiklarna betraktas i huvudsak tre olika typer av problem relaterade till kromatografiska data: kvantifiering, parvis matchning och klustring. I den första artikeln utvecklas en icke-parametrisk modell för mätfel av kromatografiska analyser av alkoholhalt i blodet. I den andra artikeln utvecklas en prediktiv inferensmetod för jämförelse av två stickprov. Metoden tillämpas i den tredje artik eln för jämförelse av oljeprover i syfte att kunna identifiera den förorenande källan i samband med oljeutsläpp. I den fjärde artikeln härleds en prediktiv modell för klustring av data av blandad diskret och kontinuerlig typ, vilken bl.a. tillämpas i klassificering av amfetaminprover med avseende på produktionsomgångar.
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Bestraffning av internationella brott vid internationella och hybrida straffrättsliga domstolar har traditionellt och huvudsakligen grundat sig på principen om retributiv (vedergällande) rättvisa och ackusatorisk process snarare än återuppbyggande rättvisa och en inkvisitorisk modell. Därav har brottsoffrens ställning vid dessa straffrättsliga domstolar begränsat sig till den som innehas av vittnen vid Tribunalen som behandlar brott som begåtts i det forna Jugoslavien (ICTY), Internationella krigsförbrytartribunalen för Rwanda (ICTR) och Specialdomstolen för Sierra Leone (SCSL). Internationella brottmålsdomstolen (ICC), å sin sida, har medfört en viktig förändring gällande brottsoffrens ställning i internationella straffrättsliga fora, vilket innebär att de från att ha betraktats endast i egenskap av vittnen nu även har en rätt att delta och lämna sina synpunkter (i egenskap av brottsofferdeltagare) samt kräva gottgörelse. Denna trend har fortsatt inom området för internationell straffrätt, vilket manifesterats vid hybridtribunaler som tillsatts efter ICC såsom Kambodjadomstolen (ECCC) vid vilken brottsoffer kan agera civilrättsliga parter och Specialdomstolen för Libanon (STL) där brottsoffer kan inneha en deltagande roll. Den föreliggande studien behandlar två huvudsakliga frågeställningar, av vilka den första lyder: Vilken ställning tillskrivs brottsoffren vid internationella domstolar och hybridtribunaler? I detta hänseende argumenterar författaren, sammanfattningsvis, för att brottsoffrens ställning vid internationella straffrättsliga domstolar och hybridtribunaler huvudsakligen tar sig uttryck på tre sätt, d.v.s. som brottsoffer i egenskap av vittnen, som brottsoffer i egenskap av deltagande brottsoffer/civilrättsliga parter samt som brottsoffer som kräver gottgörelse. Den andra frågeställningen för denna studie lyder: På vilket sätt fungerar brottsoffrens ställning som vittnen, brottsofferdeltagande/civilrättsliga parter och gottgörelsekrävande vid internationella och hybrida straffrättsliga domstolar? -------------------------------------------------------------------------------------------------------------------------------------------------- Kansainvälisten rikosten rankaiseminen kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa on perinteisesti enimmäkseen perustunut retributiivisen oikeuden ja akkusatorisen menetelmän soveltamiseen pikemmin kuin restoratiivisen oikeuden ja inkvisitorisen menetelmän soveltamiseen. Niinpä uhrien asema kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa on rajoittunut todistajan asemaan entisen Jugoslavian kansainvälisessä sotarikostuomioistuimessa (ICTY), Ruandan kansainvälisessä sotarikostuomioistuimessa (ICTR) ja Sierra Leonen erikoistuomioistuimessa (SCSL). Kansainvälisen rikostuomioistuimen (ICC) perustaminen on kuitenkin merkinnyt tärkeää muutosta uhrien asemaan kansainvälisen rikosoikeuden alalla siten, että kun uhrit aiemmin nähtiin vain todistajina, heillä on nyt myös mahdollisuus tuoda esiin omat näkökantansa (osallistumisoikeus) ja vaatia hyvitystä. Tämä suuntaus on jatkunut kansainvälisen rikosoikeuden alalla ICC:n jälkeen perustetuissa hybridituomioistuimissa, kuten Kambodzhan erityistuomioistuimessa (ECCC), missä uhrit voivat olla asianosaisen asemassa, sekä Libanonin erityistuomioistuimessa (STL), missä uhrit voivat osallistua prosessiin. Tämä tutkimus käsittelee kahta keskeistä kysymystä. Ensinnäkin: Mikä on rikoksen uhrien asema kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa? Tutkimuksessa päädytään mm. siihen, että uhrien asema kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa voi koostua pääosin kolmesta ulottuvuudesta eli uhrit todistajina, uhrit prosessiin osallistujina/asianosaisina ja uhrit hyvityksen hakijoina. Tutkimuksen toinen keskeinen kysymys on: Miten uhrien asema todistajina, prosessiin osallistujina/ asianosaisina ja hyvityksen hakijoina toimii kansainvälisissä rikostuomioistuimissa ja hybridituomioistuimissa?
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Biofuels for transport are a renewable source of energy that were once heralded as a solution to multiple problems associated with poor urban air quality, the overproduction of agricultural commodities, the energy security of the European Union (EU) and climate change. It was only after the Union had implemented an incentivizing framework of legal and political instruments for the production, trade and consumption of biofuels that the problems of weakening food security, environmental degradation and increasing greenhouse gases through land-use changes began to unfold. In other words, the difference between political aims for why biofuels are promoted and their consequences has grown – which is also recognized by the EU policy-makers. Therefore, the global networks of producing, trading and consuming biofuels may face a complete restructure if the European Commission accomplishes its pursuit to sideline crop-based biofuels after 2020. My aim with this dissertation is not only to trace the manifold evolutions of the instruments used by the Union to govern biofuels but also to reveal how this evolution has influenced the dynamics of biofuel development. Therefore, I study the ways the EU’s legal and political instruments of steering biofuels are coconstitutive with the globalized spaces of biofuel development. My analytical strategy can be outlined through three concepts. I use the term ‘assemblage’ to approach the operations of the loose entity of actors and non-human elements that are the constituents of multi-scalar and -sectorial biofuel development. ‘Topology’ refers to the spatiality of this European biofuel assemblage and its parts whose evolving relations are treated as the active constituents of space, instead of simply being located in space. I apply the concept of ‘nomosphere’ to characterize the framework of policies, laws and other instruments that the EU applies and construes while attempting to govern biofuels. Even though both the materials and methods vary in the independent articles, these three concepts characterize my analytical strategy that allows me to study law, policy and space associated with each other. The results of my examinations underscore the importance of the instruments of governance of the EU constituting and stabilizing the spaces of producing and, on the other hand, how topological ruptures in biofuel development have enforced the need to reform policies. This analysis maps the vast scope of actors that are influenced by the mechanism of EU biofuel governance and, what is more, shows how they are actively engaging in the Union’s institutional policy formulation. By examining the consequences of fast biofuel development that are spatially dislocated from the established spaces of producing, trading and consuming biofuels such as indirect land use changes, I unfold the processes not tackled by the instruments of the EU. Indeed, it is these spatially dislocated processes that have pushed the Commission construing a new type of governing biofuels: transferring the instruments of climate change mitigation to land-use policies. Although efficient in mitigating these dislocated consequences, these instruments have also created peculiar ontological scaffolding for governing biofuels. According to this mode of governance, the spatiality of biofuel development appears to be already determined and the agency that could dampen the negative consequences originating from land-use practices is treated as irrelevant.
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A study has been conducted focusing on how the phosphorus renrx)val efficiency of a constructed wetland (CW) can be optimized through the selective enrichment of the substratum. Activated alumina and powdered iron were examined as possible enrichment compounds. Using packed glass column trials it was found that alumina was not suitable for the renx)val of ortho-phosphate from solution, while mixtures of powdered iron and quartz sand proved to be very efficient. The evaluation of iron/sand mixtures in CWs planted with cattails was performed in three stages; first using an indoor lab scale wetland, then an outdoor lab scale wetland, and finally in a small scale pilot project. For the lab scale tests, three basic configurations were evaluated: using the iron/sand as a pre-filter, in the root bed. and as a post filter. Primary lagoon effluent was applied to the test cells to simulate actual CW conditions, and the total phosphorus and iron concentrations of the influent and effluent were nfK)nitored. The pilot scale trials were limited to using only a post filter design, due to in-progress research at the pilot site. The lab scale tests achieved average renrK>val efficiencies greater than 91% for all indoor configurations, and greater than 97% for all outdoor configurations. The pilot scale tests had an average renK)val efficiency of 60%. This relatively low efficiency in the pilot scale can be attributed to the post filters being only one tenth the size of the lab scale test in terms of hydraulic loading (6 cm/day vs. 60 cm/day).
Investigations towards the synthesis of isotope labelled analogues of tocopherols and tocotrienols /
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Vitamin E is considered as the most effective lipophilic chain breaking antioxidant. a-Tocopherol and its analogues have been studied thoroughly with regards to its biokinetics and bioavailabily. Deuterated tocopherols have been synthesized and utilized in such studies. Tocotrienols are arousing more and more interest because of their high efficiency as antioxidants. However, to date, there is no effective synthetic method reported for deuterated tocotrienols. This thesis is focused on the investigation of the synthetic methods of deuterated tocotrienols and their analogues: 5-trideuteromethyl-a-tocotrienol, 5- trideuteromethyl-p-tocotrienol, tocotrienol acetate, silyl tocotrienol ether, etc. Several synthetic procedures for the preparation of poly-deuterated tocopherols are known. Mainly the deuterium is introduced by use of labelled formaldehyde and deuterated hydrogen chloride under Lewis acid catalysis. However, these methods are not effective in tocotrienols due to exchange of protons for deuterium at other sites under the acidic conditions. We developed several different approaches to generate polydeuterated tocotrienols by using both morpholinomethylation followed by reduction with NaCNBDs as deuterated reducing reagents and transmetalation strategy. The 5-trideuteromethyl-a-tocotrienol was finally obtained in a satisfactory yield of 60%. In addition, this thesis also discussed the study of structural comparison and the chemical property difference of tocopherols and tocotrienols, which provides hints to explain the reactivity difference of them towards oxidation at the C3-C4 positions.Furthermore, the methodology of halogenation and dehydrohalogenation of tocotrienol was explored to prepare a hexaene tocotrienol derivative as a florescent reporter of tocopherol.
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Investigations of 2-alkyl-3-methoxypyrazines (2-isopropyl-3-methoxypyra2ine, 2- secbutyl-3-methoxypyrazine and 2-isobutyl-3-niethoxypyrazine) in ladybug species {Coleoptera: Coccinellidae) and wine samples have been conducted. Headspace sampling coupled with gas chromatography-mass spectrometry was used to determine amounts of 2-alkyl-3-methoxypyra2ines in the ladybug species. Hippodamia convergens had the highest amount of alkybnethoxypyrazines, followed by Harmoma axyridis and the least in Coccinella septempunctata. Using a solvent extraction method, the precoccinelline alkaloid was found present in Hippodamia convergens and Coccinella septempunctata but not Harmonia axyridis. Steam distillation followed by a soHd phase extraction method as a sample preparation technique, enhanced detection while the isotope dilution method afforded accurate quantitation of the alkyknethoxypyrazines in the wine samples. Both ladybug-tainted and commercial wine samples were found to contain the 2- alkyl-3-methoxypyrazines. Wine samples prepared in 2001 generally contained higher levels than the corresponding 2003 samples. Levels of the 2-alkyl-3-methoxypyrazines found in the commercial wines ranged from a minimum value of 6 ng/L to 260 ±10 ng/L. Analyses revealed that for both ladybug species and wine samples, the 2- isopropyl-3-methoxypyrazine had the highest concentration, followed by 2-isobutyl- 3-methoxypyrazine and the least being the 2-secbutyl-3-methoxypyrazine. Possible contamination of the wine samples by ladybugs is thoroughly discussed. Furthermore, attempts to remove or reduce the levels of the alkylmethoxypyrazines with molecularly imprinted polymers from wine samples are presented in detail.
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Factors affecting the detennination of PAHs by capillary GC/MS were studied. The effect of the initial column temperature and the injection solvent on the peak areas and heights of sixteen PAHs, considered as priority pollutants, USillg crosslinked methyl silicone (DB!) and 5% diphenyl, 94% dimethyl, 1% vinyl polysiloxane (DBS) columns was examined. The possibility of using high boiling point alcohols especially butanol, pentanol, cyclopentanol, and hexanol as injection solvents was investigated. Studies were carried out to optimize the initial column temperature for each of the alcohols. It was found that the optimum initial column temperature is dependent on the solvent employed. The peak areas and heights of the PAHs are enhanced when the initial column temperature is 10-20 c above the boiling point of the solvent using DB5 column, and the same or 10 C above the boiling point of the solvent using DB1 column. Comparing the peak signals of the PAHs using the alcohols, p-xylene, n-octane, and nonane as injection solvents, hexanol gave the greatest peak areas and heights of the PAHs particularly the late-eluted peaks. The detection limits were at low pg levels, ranging from 6.0 pg for fluorene t9 83.6 pg for benzo(a)pyrene. The effect of the initial column temperature on the peak shape and the separation efficiency of the PARs was also studied using DB1 and DB5 columns. Fronting or splitting of the peaks was obseIVed at very low initial column temperature. When high initial column temperature was used, tailing of the peaks appeared. Great difference between DB! and.DB5 columns in the range of the initial column temperature in which symmetrical.peaks of PAHs can be obtained is observed. Wider ranges were shown using DB5 column. Resolution of the closely-eluted PAHs was also affected by the initial column temperature depending on the stationary phase employed. In the case of DB5, only the earlyeluted PAHs were affected; whereas, with DB1, all PAHs were affected. An analytical procedure utilizing solid phase extraction with bonded phase silica (C8) cartridges combined with GC/MS was developed to analyze PAHs in water as an alternative method to those based on the extraction with organic solvent. This simple procedure involved passing a 50 ml of spiked water sample through C8 bonded phase silica cartridges at 10 ml/min, dried by passing a gentle flow of nitrogen at 20 ml/min for 30 sec, and eluting the trapped PAHs with 500 Jll of p-xylene at 0.3 ml/min. The recoveries of PAHs were greater than 80%, with less than 10% relative standard deviations of nine determinations. No major contaminants were present that could interfere with the recognition of PAHs. It was also found that these bonded phase silica cartridges can be re-used for the extraction of PAHs from water.