Análise do teor de cocaína em amostras apreendidas pela polícia utilizando-se a técnica de cromatografia liquida de alta eficiência com detector UV-Vis

A técnica de CLAE com detecção UV-Vis foi empregada na análise do teor de cocaína em amostras apreendidas de cocaína e crack. Uma fase móvel de acetonitrila/água (95:5v/v) possibilitou um sinal de pico para a cocaína em 3,5 minutos. O sinal espectrofotométrico otimizado foi obtido em um comprimento de onda de 224 nm. A curva analítica de 1,0 a 40,0 ppm para cocaína foi obtida, exibindo um coeficiente de correlação linear de 0,9989, com limites de detecção e quantificação de 0,75 e 3,78 ppm, respectivamente. Esta metodologia foi aplicada na dosagem de amostras confiscadas de cocaína e crack no Laboratório de Polícia Científica de Ribeirão Preto-SP.

Combining Near-Field and Far-Field Microscopy: A new method for nanoscale super-resolution imaging

Lähikenttä- ja kaukokenttämikroskopian yhdistäminen: Uusi korkearesoluutioinen menetelmä nanokuvantamiseen. Osteoporoosi on sairaus, jossa luun uudistumisprosessi ei ole enää tasapainossa. Uuden luun muodostuminen on hitaampaa johtuen osteoblastien laskeneesta aktiivisuudesta. Yksi keino estää osteoporoosin syntyä on estää osteoklastien sitoutuminen luun pinnalle, jolloin ne eivät aloita luun syömisprosessia. Tämän Pro gradu -tutkielman tarkoituksena on luoda uusi työkalu osteoklastien sitoutumisen tutkimiseen samanaikaisesti fluoresenssi- ja atomivoimamikroskoopilla. Tätä tarkoitusta varten yhdistettiin atomivoimamikroskooppi sekä STED mikroskooppi. Kirjallisuuskatsauksessa käydään läpi yksityiskohtaisesti molempien mikroskooppitekniikoiden teoriat. Kokeellisessa osiossa esitetään käytetyt metodit ja alustavat tulokset uudella systeemillä. Lisäksi keskustellaan lyhyesti kuvan analysoinnista ImageJohjelmalla. Konfokaalisen fluoresenssimikroskoopin ja atomivoimamikroskoopin yhdistelmä on keksitty jo aikaisemmin, mutta tavallisen konfokaalimikroskoopin erottelukyvyn raja on noin 200 nanometriä johtuen valon diffraktioluonteesta. Yksityiskohdat eivät erotu, jos ne ovat pienempiä kuin puolet käytettävästä aallonpituudesta. STED mikroskooppi mahdollistaa fluoresenssikuvien taltioimisen solunsisäisistä prosesseista 50 nanometrin lateraalisella erotuskyvyllä ja atomivoimamikroskooppi antaa topografista tietoa näytteestä nanometrien erotuskyvyllä. Biologisia näytteitä kuvannettaessa atomivoimamikroskoopin erotuskyky kuitenkin huononee ja yleensä saavutetaan 30-50 nanometrin erotuskyky. Kuvien kerrostaminen vaatii vertauspisteitä ja tätä varten käytettiin atomivoimamikroskoopin kärjen tunnistamista ja referenssipartikkeleita. Kuva-analysointi suoritettiin ImageJ-kuvankäsittelyohjelmalla. Tuloksista nähdään, että referenssipartikkelit ovat hyviä, mutta niiden sijoittaminen tarkasti tietylle kohdealueelle on hankalaa nanoskaalassa. Tästä johtuen kärjen havaitseminen fluoresenssikuvassa on parempi metodi. Atomivoimamikroskoopin kärki voidaan päällystää fluoresoivalla aineella, mutta tämä lisää kärjen aiheuttamaa konvoluutiota mittausdataan. Myös valon takaisinsirontaa kärjestä voidaan tutkia, jolloin konvoluutio ei lisäänny. Ensimmäisten kuvien kerrostamisessa käytettiin hyväksi fluoresoivalla aineella päällystettyä kärkeä ja lopputuloksessa oli vain 50 nanometrin yhteensopimattomuus fluoresenssi- ja topografiakuvan kanssa. STED mikroskoopin avulla nähdään leimattujen proteiinien tarkat sijainnit tiettynä ajankohtana elävän solun sisällä. Samaan aikaan pystytään kuvantamaan solun fyysisiä muotoja tai mitata adheesiovoimia atomivoimamikroskoopilla. Lisäksi voidaan käyttää funktinalisoitua kärkeä, jolla voidaan laukaista signalointitapahtumia solun ja soluväliaineen välillä. Sitoutuminen soluväliaineeseen voidaan rekisteröidä samoin kuin adheesiomediaattorien sijainnit sitoutumisalueella. Nämä dynaamiset havainnot tuottavat uutta informaatiota solun signaloinnista, kun osteoklasti kiinnittyy luun pintaan. Tämä teknologia tarjoaa uuden näkökulman monimutkaisiin signalointiprosesseihin nanoskaalassa ja tulee ratkaisemaan lukemattoman määrän biologisia ongelmia.

Four to the Floor // (Far) Below the Bassline

http://www.fanniniemi-junkola.com/oneandmany.html ja https://www.facebook.com/events/363052333825773/ (15.1.2014)

Simulation of new p-type pixel strip detector with enhanced multiplication effect

This Master’s Thesis is dedicated to the simulation of new p-type pixel strip detector with enhanced multiplication effect. It is done for high-energy physics experiments upgrade such as Super Large Hadron Collider especially for Compact Muon Solenoid particle track silicon detectors. These detectors are used in very harsh radiation environment and should have good radiation hardness. The device engineering technology for developing more radiation hard particle detectors is used for minimizing the radiation degradation. New detector structure with enhanced multiplication effect is proposed in this work. There are studies of electric field and electric charge distribution of conventional and new p-type detector under reverse voltage bias and irradiation. Finally, the dependence of the anode current from the applied cathode reverse voltage bias under irradiation is obtained in this Thesis. For simulation Silvaco Technology Computer Aided Design software was used. Athena was used for creation of doping profiles and device structures and Atlas was used for getting electrical characteristics of the studied devices. The program codes for this software are represented in Appendixes.

Regulation of the expression of NADP-malic enzyme by UV-B, red and far-red light in maize seedlings

The induction of nicotinamide adenine dinucleotide phosphate-malic enzyme (NADP-ME) in etiolated maize (Zea mays) seedlings by UV-B and UV-A radiation, and different levels of photosynthetically active radiation (PAR, 400-700 nm) was investigated by measuring changes in activity, protein quantity and RNA levels as a function of intensity and duration of exposure to the different radiations. Under low levels of PAR, exposure to UV-B radiation but not UV-A radiation for 6 to 24 h caused a marked increase in the enzyme levels similar to that observed under high PAR in the absence of UV-B. UV-B treatment of green leaves following a 12-h dark period also caused an increase in NADP-ME expression. Exposure to UV-B radiation for only 5 min resulted in a rapid increase of the enzyme, followed by a more gradual rise with longer exposure up to 6 h. Low levels of red light for 5 min or 6 h were also effective in inducing NADP-ME activity equivalent to that obtained with UV-B radiation. A 5-min exposure to far-red light following UV-B or red light treatment reversed the induction of NADP-ME, and this effect could be eliminated by further treatment with UV-B or red light. These results indicate that physiological levels of UV-B radiation can have a positive effect on the induction of this photosynthetic enzyme. The reducing power and pyruvate generated by the activity of NADP-ME may be used for respiration, in cellular repair processes and as substrates for fatty acid synthesis required for membrane repair.

Modeling Front End Electronics for a Gas Electron Multiplier Detector

The Large Hadron Collider (LHC) in The European Organization for Nuclear Research (CERN) will have a Long Shutdown sometime during 2017 or 2018. During this time there will be maintenance and a possibility to install new detectors. After the shutdown the LHC will have a higher luminosity. A promising new type of detector for this high luminosity phase is a Triple-GEM detector. During the shutdown these detectors will be installed at the Compact Muon Solenoid (CMS) experiment. The Triple-GEM detectors are now being developed at CERN and alongside also a readout ASIC chip for the detector. In this thesis a simulation model was developed for the ASICs analog front end. The model will help to carry out more extensive simulations and also simulate the whole chip before the whole design is finished. The proper functioning of the model was tested with simulations, which are also presented in the thesis.

Readout architectures for hybrid pixel detector readout chips

The original contribution of this thesis to knowledge are novel digital readout architectures for hybrid pixel readout chips. The thesis presents asynchronous bus-based architecture, a data-node based column architecture and a network-based pixel matrix architecture for data transportation. It is shown that the data-node architecture achieves readout efficiency 99% with half the output rate as a bus-based system. The network-based solution avoids “broken” columns due to some manufacturing errors, and it distributes internal data traffic more evenly across the pixel matrix than column-based architectures. An improvement of > 10% to the efficiency is achieved with uniform and non-uniform hit occupancies. Architectural design has been done using transaction level modeling (TLM) and sequential high-level design techniques for reducing the design and simulation time. It has been possible to simulate tens of column and full chip architectures using the high-level techniques. A decrease of > 10 in run-time is observed using these techniques compared to register transfer level (RTL) design technique. Reduction of 50% for lines-of-code (LoC) for the high-level models compared to the RTL description has been achieved. Two architectures are then demonstrated in two hybrid pixel readout chips. The first chip, Timepix3 has been designed for the Medipix3 collaboration. According to the measurements, it consumes < 1 W/cm^2. It also delivers up to 40 Mhits/s/cm^2 with 10-bit time-over-threshold (ToT) and 18-bit time-of-arrival (ToA) of 1.5625 ns. The chip uses a token-arbitrated, asynchronous two-phase handshake column bus for internal data transfer. It has also been successfully used in a multi-chip particle tracking telescope. The second chip, VeloPix, is a readout chip being designed for the upgrade of Vertex Locator (VELO) of the LHCb experiment at CERN. Based on the simulations, it consumes < 1.5 W/cm^2 while delivering up to 320 Mpackets/s/cm^2, each packet containing up to 8 pixels. VeloPix uses a node-based data fabric for achieving throughput of 13.3 Mpackets/s from the column to the EoC. By combining Monte Carlo physics data with high-level simulations, it has been demonstrated that the architecture meets requirements of the VELO (260 Mpackets/s/cm^2 with efficiency of 99%).

Spectrally Tuned Lanthanide Photoluminescence for Point-of-Care Testing

Point-of-care (POC) –diagnostics is a field with rapidly growing market share. As these applications become more widely used, there is an increasing pressure to improve their performance to match the one of a central laboratory tests. Lanthanide luminescence has been widely utilized in diagnostics because of the numerous advantages gained by the utilization of time-resolved or anti-Stokes detection. So far the use of lanthanide labels in POC has been scarce due to limitations set by the instrumentation required for their detection and the shortcomings, e.g. low brightness, of these labels. Along with the advances in the research of lanthanide luminescence, and in the field of semiconductors, these materials are becoming a feasible alternative for the signal generation also in the future POC assays. The aim of this thesis was to explore ways of utilizing time-resolved detection or anti-Stokes detection in POC applications. The long-lived fluorescence for the time-resolved measurement can be produced with lanthanide chelates. The ultraviolet (UV) excitation required by these chelates is cumbersome to produce with POC compatible fluorescence readers. In this thesis the use of a novel light-harvesting ligand was studied. This molecule can be used to excite Eu(III)-ions at wavelengths extending up to visible part of the spectrum. An enhancement solution based on this ligand showed a good performance in a proof-of-concept -bioaffinity assay and produced a bright signal upon 365 nm excitation thanks to the high molar absorptivity of the chelate. These features are crucial when developing miniaturized readers for the time-resolved detection of fluorescence. Upconverting phosphors (UCPs) were studied as an internal light source in glucose-sensing dry chemistry test strips and ways of utilizing their various emission wavelengths and near-infrared excitation were explored. The use of nanosized NaYF :Yb3+,Tm3+-particles enabled the replacement of an external UV-light source with a NIR-laser and gave an additional degree of freedom in the optical setup of the detector instrument. The new method enabled a blood glucose measurement with results comparable to a current standard method of measuring reflectance. Microsized visible emitting UCPs were used in a similar manner, but with a broad absorbing indicator compound filtering the excitation and emission wavelengths of the UCP. This approach resulted in a novel way of benefitting from the non-linear relationship between the excitation power and emission intensity of the UCPs, and enabled the amplification of the signal response from the indicator dye.

Generative Part-Based Gabor Object Detector

Object detection is a fundamental task of computer vision that is utilized as a core part in a number of industrial and scientific applications, for example, in robotics, where objects need to be correctly detected and localized prior to being grasped and manipulated. Existing object detectors vary in (i) the amount of supervision they need for training, (ii) the type of a learning method adopted (generative or discriminative) and (iii) the amount of spatial information used in the object model (model-free, using no spatial information in the object model, or model-based, with the explicit spatial model of an object). Although some existing methods report good performance in the detection of certain objects, the results tend to be application specific and no universal method has been found that clearly outperforms all others in all areas. This work proposes a novel generative part-based object detector. The generative learning procedure of the developed method allows learning from positive examples only. The detector is based on finding semantically meaningful parts of the object (i.e. a part detector) that can provide additional information to object location, for example, pose. The object class model, i.e. the appearance of the object parts and their spatial variance, constellation, is explicitly modelled in a fully probabilistic manner. The appearance is based on bio-inspired complex-valued Gabor features that are transformed to part probabilities by an unsupervised Gaussian Mixture Model (GMM). The proposed novel randomized GMM enables learning from only a few training examples. The probabilistic spatial model of the part configurations is constructed with a mixture of 2D Gaussians. The appearance of the parts of the object is learned in an object canonical space that removes geometric variations from the part appearance model. Robustness to pose variations is achieved by object pose quantization, which is more efficient than previously used scale and orientation shifts in the Gabor feature space. Performance of the resulting generative object detector is characterized by high recall with low precision, i.e. the generative detector produces large number of false positive detections. Thus a discriminative classifier is used to prune false positive candidate detections produced by the generative detector improving its precision while keeping high recall. Using only a small number of positive examples, the developed object detector performs comparably to state-of-the-art discriminative methods.

Conversion of hydroxycinnamic acids into volatile phenols in a synthetic medium and in red wine by Dekkera bruxellensis

The conversion of p-coumaric acid, ferulic acid, and caffeic acid into 4-ethylphenol, 4-ethylguaiacol and 4-ethylcatechol was studied in Dekkera bruxellensis ISA 1791 under defined conditions in a synthetic medium and in a red wine. Liquid chromatography (HPLC-DAD) was used to quantify the phenolic acids, and gas chromatography (GC) coupled to a FID detector was used to quantify volatile phenols using a novel analytical methodology that does not require sample derivatization. Identification was achieved by gas chromatography-mass detection (GC-MS). The results show that phenolic acids concentration decreases while volatile phenols concentration increases. The proportion of caffeic acid taken up by Dekkera bruxellensis is lower than that for p-coumaric or ferulic acid; therefore less 4-ethylcatechol is formed. More important, 4-ethylcathecol synthesis by Dekkera bruxellensis in wine has never been demonstrated so far. These results contribute decisively to a better understanding of the origin of the volatile phenols in wines. The accumulation of these compounds in wine is nowadays regarded as one of the key factors of quality control.

Comparison of baseline data between chronic kidney disease patients starting hemodialysis who live near and far from the dialysis center

Introduction: The treatment offered to chronic kidney disease (CKD) patients before starting hemodialysis (HD) impacts prognosis. Objective: We seek differences among incident HD patients according to the distance between home and the dialysis center. Methods: We included 179 CKD patients undergoing HD. Patients were stratified in two groups: "living near the dialysis center" (patients whose hometown was in cities up to 100 km from the dialysis center) or as "living far from the dialysis center" (patients whose hometown was more than 100 km from the dialysis center). Socioeconomic status, laboratory results, awareness of CKD before starting HD, consultation with nephrologist before the first HD session, and type of vascular access when starting HD were compared between the two groups. Comparisons of continuous and categorical variables were performed using Student's t-test and the Chi-square test, respectively. Results: Ninety (50.3%) patients were classified as "living near the dialysis center" and 89 (49.7%) as "living far from the dialysis center". Patients living near the dialysis center were more likely to know about their condition of CKD than those living far from the dialysis center, respectively 46.6% versus 28.0% (p = 0.015). Although without statistical significance, patients living near the dialysis center had more frequent previous consultation with nephrologists (55.5% versus 42.6%; p = 0.116) and first HD by fistula (30.0% versus 19.1%; p = 0.128) than those living far from the dialysis center. Conclusion: There are potential advantages of CKD awareness, referral to nephrologists and starting HD through fistula among patients living near the dialysis center.

”Far from being such untameable savages” - Australian ja Uuden-Seelannin alkuperäiskansat Britannian parlamentin komitearaporteissa 1830- ja 40-luvuilla

Käsittelen tutkielmassani Australian aboriginaaleista ja Uuden-Seelannin maoreista 1830- ja 1840-luvuilla Britannian hallinnossa esitettyjä kuvauksia. Lähteenä aiheen tarkasteluun käytän viiden Britannian parlamentin tuona aikana asettaman komitean raportteja, joissa käsitellään Australian ja Uuden-Seelannin tilaa suhteessa eurooppalaisiin siirtolaisiin ja näiden alueiden kolonisoimista. Yhdessä nämä viisi raporttia muodostavat kiinnostavan kokonaisuuden, sillä ne ovat 1800-luvun ensimmäisen puoliskon ainoat komitearaportit, joissa käsitellään aboriginaaleja ja maoreja. Ne olivat myös yksi tapa, jolla 1800-luvulla siirtokunnista saatiin tietoa Britannian hallintoon, joten niissä esitetyt kuvaukset olivat merkittävä osa tiedonkulkua siirtokunnista imperiumin metropoliin. Tutkielmassani selvitän millaista kuvaa komiteat loivat aboriginaaleista ja maoreista metropolissa toimineelle hallinnolle siirtomaista peräisin olleiden lähteiden perusteella. Tarkastelen komiteoiden raporteissaan esittämiä kuvauksia aboriginaaleista ja maoreista suhteessa komiteoita ympäröineeseen ajatteluun ja muiden käsittelemieni komiteoiden esittämiin näkemyksiin. Rinnastamalla raporteissa esitettyjä kuvauksia ja näkemyksiä laajempaan aikalaiseen ajatteluun pystyn tuomaan esille komiteoiden esittämistä näkemyksistä niin samankaltaisuuksia verrattuna laajempaan ajatteluun kuin ajalleen poikkeuksellisia näkemyksiä. Komiteoiden esittämien näkemysten suhteuttaminen myös raporttien taustalla olleisiin todistajalausuntoihin tuo esille komiteoiden omia suuntautumisia. Komiteoiden raporteissa aboriginaalit ja maorit näyttäytyvät keskenään hyvin erilaisina kansoina monilla eri perusteilla. Maoreista luodaan raporteissa kuvaa aboriginaaleja kehittyneempinä ja sivistyneempinä, mikä perustuu niin maorien kehittyneempiin elinkeinoihin, yhteiskunnalliseen organisoitumiseen, kykeneväisyyteen toimia aktiivisena osapuolena kanssakäymisessä eurooppalaisten kanssa ja toisaalta aboriginaalien jo alunalkaen alhaiseen tilaan. Eri raportit kuitenkin kuvaavat maoreja ja aboriginaaleja kuitenkin hyvin eri tavoilla, ja erityisesti komiteoiden omat motiivit ja tavoitteet näyttävät vaikuttaneen tapoihin, joilla näitä kansoja kuvataan. Voimakkaana vastakkainasetteluna näyttäytyy humanitaarinen, lähetystyötä korostava positiivisempi tapa kuvata kansoja ja kolonisaatiota sekä siirtolaisten etuja ajaneet negatiivisemmat kuvaukset. Komiteoiden käsittely kuitenkin perustuu lähes täysin eurooppalaiseen näkökulmaan ja eurooppalaisiin normeihin, eikä näiden kansojen kulttuuria tuoda juurikaan esille.