8 resultados para tracking of explosives

em Helda - Digital Repository of University of Helsinki


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Cardiovascular diseases (CVDs) are the leading cause of mortality in the world. Studies of the impact of single nutrients on the risk for CVD have often provided inconclusive results, and recent research in nutritional epidemiology with a more holistic whole-diet approach has proven fruitful. Moreover, dietary habits in childhood and adolescence may play a role in later health and disease, either independently or by tracking into adulthood. The main aims of this study were to find childhood and adulthood determinants of adulthood diet, to identify dietary patterns present among the study population and to study the associations between long-term food choices and cardiovascular health in young Finnish adults. The study is a part of the multidisciplinary Cardiovascular Risk in Young Finns study, which is an ongoing, prospective cohort study with a 21-year follow-up. At baseline in 1980, the subjects were children and adolescents aged 3 to 18 years (n included in this study = 1768), and young adults aged 24 to 39 years at the latest follow-up study in 2001 (n = 1037). Food consumption and nutrient intakes were assessed with repeated 48-hour dietary recalls. Other determinations have included comprehensive risk factor assessments using blood tests, physical measurements and questionnaires. In the latest follow-up, ultrasound examinations were performed to study early atherosclerotic vascular changes. The average intakes showed substantial changes since 1980. Intakes of fat and saturated fat had decreased, whereas the consumption of fruits and vegetables had increased. Intake of fat and consumption of vegetables in childhood and physical activity in adulthood were important health behavioural determinants of adult diet. Additionally, a principal component analysis was conducted to identify major dietary patterns at each study point. A similar set of two major patterns was recognised throughout the study. The traditional dietary pattern positively correlated with the consumption of traditional Finnish foods, such as rye, potatoes, milk, butter, sausages and coffee, and negatively correlated with fruit, berries and dairy products other than milk. This type of diet was independently associated with several risk factors of CVD, such as total and low-density lipoprotein cholesterol, apolipoprotein B and C-reactive protein concentrations among both genders, as well as with systolic blood pressure and insulin levels among women. The traditional pattern was also independently associated with intima media thickness (IMT), a subclinical predictor of CVD, in men but not in women. The health-conscious pattern, predominant among female subjects, non-smokers and urbanites, was characterised by more health-conscious food choices such as vegetables, legumes and nuts, tea, rye, fish, cheese and other dairy products, as well as by the consumption of alcoholic beverages. This pattern was inversely, but less strongly, associated with cardiovascular risk factors. Tracking of the dietary pattern scores was observed, particularly among subjects who were adolescents at baseline. Moreover, a long-term high intake of protein concurrent with a low intake of fat was positively associated with IMT. These findings suggest that food behaviour and food choices are to some extent established as early as in childhood or adolescence and may significantly track into adulthood. Long-term adherence to traditional food choices seems to increase the risk for developing CVD, especially among men. Those with intentional or unintentional low fat diets, but with high intake of protein may also be at increased risk for CVD. The findings offer practical, food-based information on the relationship between diet and CVD and encourage further use of the whole-diet approach in epidemiological research. The results support earlier findings that long-term food choices play a role in the development of CVD. The apparent influence of childhood habits is important to bear in mind when planning educational strategies for the primary prevention of CVD. Further studies on food choices over the entire lifespan are needed.

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Uveal melanoma (UM) is the most common primary ocular malignancy in adults. In Finland, approximately 50 new cases are diagnosed yearly. Up to 50% of UM metastasize, mostly to the liver, although other organs are also affected. Despite improvements in the management of the primary tumour, the survival rates of patients with metastatic UM are poor. Until the 1970s, UMs were treated by enucleation i.e. removal of the eye. Currently, UM is usually treated by brachytherapy, which is known to influence tumour cells and blood vessels. UMs enucleated both primarily and secondarily after brachytherapy contain tumour-infiltrating macrophages, and a high number of macrophages in primary UM is associated with a shorter survival and a higher microvascular density (MVD) within the tumour tissue. The latter is independently associated with a shorter time to metastatic death. Macrophages have several diverse roles depending on their response to variable signals from the surrounding microenvironment. They function as scavengers, as producers of angiogenic and growth factors as well as proteases, which modulate extracellular matrix. Thus, tumour invasiveness and the risk for metastasis increase with increasing macrophage density. The aim of this study was to evaluate the effects of regression and progression of UM on macrophage numbers and microcirculation factors. Tumour regression is induced by primary brachytherapy, and tumour progression is evidenced by the development of metastases. Understanding the biological behaviour of UMs in the both states may help us in finding new treatment modalities against this disease. To achieve these aims case-control analyses of irradiated UMs and primarily-enucleated eyes (34 matched pairs) were performed. UMs were stained immunohistochemically to detect macrophages, extravascular matrix (EVM) loops and networks, and MVD. Following brachytherapy, a lower MVD was observed. The average number of macrophages remained unchanged. Considering that irradiated melanomas may still contain proliferating tumour cells, a clinically-relevant consequence of my study would be the reassurance that the risk for metastasis is likely to be reduced, given that the low MVD in untreated UMs indicates a favourable prognosis. The effect of progression on macrophages was studied in a paired analysis of primarily-enucleated UM and their corresponding hepatic metastases (48 pairs). A cross-sectional histopathological analysis of these pairs was carried out by staining both specimens in a similar way to the first study. MVD was greater in hepatic metastases than in corresponding primary tumours, and the survival of the patient tended to be shorter if hepatic metastases had a higher MVD. Hepatic metastases had also more dendritic macrophages than the primary UMs. Thus, the progression to metastasis seems to alter the inflammatory status within the tumour. Furthermore, determining MVD of biopsied hepatic metastases may serve as a supplementary tool in estimating the prognosis of patients with metastatic uveal melanoma. After irradiation, the majority of treated eyes have been clinically observed to have pigmented episcleral deposits. A noncomparative clinical case series of 211 irradiated UM eyes were studied by recording the number and location of pigmented episcleral deposits during follow-up visits after brachytherapy. For the first time, the study described pigmented episcleral deposits, which are found in the most UM eyes after brachytherapy, and proved them to consist of macrophages full with engulfed melanin particles. This knowledge may save patients from unnecessary enucleation, because episcleral pigmented deposits might be mistaken for extrascleral tumour growth. The presence of pigmented macrophage-related episcleral deposits was associated with plaque size and isotope rather than with tumour size, suggesting that, in addition to tumour regression, radiation atrophy of retinal pigment epithelium and choroid contributes to the formation of the deposits. In the paired (the same 34 pairs as in the first study) cross-sectional study of irradiated and non-irradiated UMs, clinically-visible episcleral deposits and migrating macrophages in other extratumoral tissues were studied histopathologically. Resident macrophages were present in extratumoral tissues in eyes with both irradiated and non-irradiated UM. Irradiation increased both the number of CD68+ macrophages in the sclera beneath the tumour and the number of clinically-observed episcleral macrophages aggregates. Brachytherapy seemed to alter the route of migration of macrophages: after irradiation, macrophages migrated preferentially through the sclera while in non-irradiated UMs they seemed to migrate more along the choroid. In order to understand the influence of these routes on tumour progression and regression in the future, labelling and tracking of activated macrophages in vivo is required.

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Syövän diagnostiikassa ja hoidossa nanopartikkelit voivat toimia kuljetinaineina lääke- ja diagnostisille aineille tai nukleiinihappojaksoille. Kantaja-aineeseen voidaan liittää kohdennusmolekyylejä partikkelien passiivista tai aktiivista kohdennusta varten tai radioleima kuvantamista tai radioterapiaa varten. Kantaja-aineiden avulla voidaan parantaa lääkeaineen fysikaalis-kemiallisia ominaisuuksia ja biologista hyötyosuutta, vähentää systeemisiä sivuvaikutuksia, pidentää lääkeaineen puoliintumisaikaa ja siten harventaa annosteluväliä, sekä parantaa lääkeaineen pääsyä kohdekudokseen. Näin voidaan parantaa kemo- ja radioterapian tehoa ja hoidon onnistumisen todennäköisyyttä. Kirjallisuuskatsauksessa perehdytään nanokantajien rooliin syövän hoidossa. Vuosikymmeniä jatkuneesta tutkimuksesta huolimatta vain kaksi (Eurooppa) tai kolme (Yhdysvallat) nanopartikkeliformulaatiota on hyväksytty markkinoille syövän hoidossa. Ongelmina ovat riittämätön hakeutuminen kohdekudokseen, immunogeenisyys ja nanopartikkelien labiilius. Kokeellisessa osassa tutkitaan in vitro ja hiirillä in vivo 99mTc-leimattujen, PEG-verhoiltujen biotiiniliposomien kaksivaiheista kohdennusta ihmisen munasarjan adenokarsinoomasoluihin. Kohdentamiseen käytetään biotinyloitua setuksimabi-(Erbitux®) vasta-ainetta, joka sitoutuu solujen yli-ilmentämiin EGF-reseptoreihin. Kaksivaiheista kohdennusta verrataan suoraan ja/tai passiiviseen kohdennukseen. Tehokkaampien kuvantamismenetelmien kehitys on vauhdittanut kohdennettujen nanopartikkelien tutkimusta. Isotooppikuvantamista käyttäen pystytään seuraamaan radioleiman jakautumista elimistössä ja kuvantamaan solutasolla tapahtuvia ilmiöitä. Kirjallisuuskatsauksessa perehdytään SPECT- ja PET-kuvantamiseen syövän hoidossa, sekä niiden hyödyntämiseen lääkekehityksessä nanopartikkelien kuvantamisessa. Kyseiset kuvantamismenetelmät erottuvat muista menetelmistä korkean erotuskyvyn, herkkyyden ja helppokäyttöisyyden suhteen. Kokeellisessa osassa 99mTc-leimattujen liposomien distribuutiota hiirissä tutkittiin SPECT-CT-laitteen avulla. Aktiivisuus kasvaimessa, pernassa ja maksassa kvantifioitiin InVivoScope-ohjelman ja gammalaskijan avulla. Tuloksia verrattiin keskenään. In vitro-kokeessa saavutettiin kaksivaiheisella kohdennuksella 2,7- 3,5-kertainen (solulinjasta riippuen) hakeutuminen soluihin kontrolliliposomeihin verrattuna. Kuitenkin suora kohdennus toimi kaksivaiheista kohdennusta paremmin in vitro. In vivo –kokeissa liposomit jakautuivat kasvaimeen tehokkaammin i.p.-annosteltuna kuin i.v.-annosteltuna. Kaksivaiheisella kohdennuksella saavutettiin 1,24-kertainen jakautuminen kasvaimeen (% ID/g kudosta) passiivisesti kohdennettuihin liposomeihin verrattuna. %ID/elin oli kohdennetuilla liposomeilla 5,9 % ja passiivisesti kohdennetuilla 5,4%. Todellinen ero oli siis pieni. InVivoScope:n ja gammalaskijan tulokset eivät korreloineet keskenään. Lisätutkimuksia ja menetelmän optimointia vaaditaan liposomien kohdennuksessa kasvaimeen.

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We present three measurements of the top-quark mass in the lepton plus jets channel with approximately 1.9 fb-1 of integrated luminosity collected with the CDF II detector using quantities with minimal dependence on the jet energy scale. One measurement exploits the transverse decay length of b-tagged jets to determine a top-quark mass of 166.9+9.5-8.5 (stat) +/- 2.9 (syst) GeV/c2, and another the transverse momentum of electrons and muons from W-boson decays to determine a top-quark mass of 173.5+8.8-8.9 (stat) +/- 3.8 (syst) GeV/c2. These quantities are combined in a third, simultaneous mass measurement to determine a top-quark mass of 170.7 +/- 6.3 (stat) +/- 2.6 (syst) GeV/c2.

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ALICE (A Large Ion Collider Experiment) is the LHC (Large Hadron Collider) experiment devoted to investigating the strongly interacting matter created in nucleus-nucleus collisions at the LHC energies. The ALICE ITS, Inner Tracking System, consists of six cylindrical layers of silicon detectors with three different technologies; in the outward direction: two layers of pixel detectors, two layers each of drift, and strip detectors. The number of parameters to be determined in the spatial alignment of the 2198 sensor modules of the ITS is about 13,000. The target alignment precision is well below 10 micron in some cases (pixels). The sources of alignment information include survey measurements, and the reconstructed tracks from cosmic rays and from proton-proton collisions. The main track-based alignment method uses the Millepede global approach. An iterative local method was developed and used as well. We present the results obtained for the ITS alignment using about 10^5 charged tracks from cosmic rays that have been collected during summer 2008, with the ALICE solenoidal magnet switched off.

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We present three measurements of the top-quark mass in the lepton plus jets channel with approximately 1.9 fb-1 of integrated luminosity collected with the CDF II detector using quantities with minimal dependence on the jet energy scale. One measurement exploits the transverse decay length of b-tagged jets to determine a top-quark mass of 166.9+9.5-8.5 (stat) +/- 2.9 (syst) GeV/c2, and another the transverse momentum of electrons and muons from W-boson decays to determine a top-quark mass of 173.5+8.8-8.9 (stat) +/- 3.8 (syst) GeV/c2. These quantities are combined in a third, simultaneous mass measurement to determine a top-quark mass of 170.7 +/- 6.3 (stat) +/- 2.6 (syst) GeV/c2.

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Research on reading has been successful in revealing how attention guides eye movements when people read single sentences or text paragraphs in simplified and strictly controlled experimental conditions. However, less is known about reading processes in more naturalistic and applied settings, such as reading Web pages. This thesis investigates online reading processes by recording participants eye movements. The thesis consists of four experimental studies that examine how location of stimuli presented outside the currently fixated region (Study I and III), text format (Study II), animation and abrupt onset of online advertisements (Study III), and phase of an online information search task (Study IV) affect written language processing. Furthermore, the studies investigate how the goal of the reading task affects attention allocation during reading by comparing reading for comprehension with free browsing, and by varying the difficulty of an information search task. The results show that text format affects the reading process, that is, vertical text (word/line) is read at a slower rate than a standard horizontal text, and the mean fixation durations are longer for vertical text than for horizontal text. Furthermore, animated online ads and abrupt ad onsets capture online readers attention and direct their gaze toward the ads, and distract the reading process. Compared to a reading-for-comprehension task, online ads are attended to more in a free browsing task. Moreover, in both tasks abrupt ad onsets result in rather immediate fixations toward the ads. This effect is enhanced when the ad is presented in the proximity of the text being read. In addition, the reading processes vary when Web users proceed in online information search tasks, for example when they are searching for a specific keyword, looking for an answer to a question, or trying to find a subjectively most interesting topic. A scanning type of behavior is typical at the beginning of the tasks, after which participants tend to switch to a more careful reading state before finishing the tasks in the states referred to as decision states. Furthermore, the results also provided evidence that left-to-right readers extract more parafoveal information to the right of the fixated word than to the left, suggesting that learning biases attentional orienting towards the reading direction.