Advanced membrane systems

Tato diplomová práce se zabývá tvorbou modelové buněčné membrány na mikrofluidním zařízení. Shrnuje postupy přípravy mikrofluidních zařízení, mechanismy tvorby fosfolipidové dvojvrstvy, faktory ovlivňující tvorbu modelové membrány a metody charakterizace těchto systémů. Zaměřuje se především na volně zavěšené planární lipidové dvojvrstvy, které jsou nejlépe přístupné různým metodám charakterizace a současně vykazují dobrou stabilitu a variabilitu. Úkolem této práce je navrhnout a připravit mikrofluidní čip, na kterém je možno připravit planární lipidovou dvojvrstvu. Představuje proto mikrofluidní zařízení připravené měkkou litografií PDMS uzpůsobené k tvorbě modelové membrány samouspořádáním fosfolipidů na rozhraní vodné a organické fáze vytvořeném díky architektuře mikrofluidního zařízení. Tvorba modelové membrány byla vizualizovaná optickou mikroskopií a zobrazováním dob života (FLIM).The diploma thesis deals with cellular membrane model preparation on microfluidic devices. It summarizes means of microfluidic device fabrication, phospholipid bilayer formation mechanisms, optimization techniques and characterization methods of those systems. It focuses on free-standing planar lipid bilayers which are easily accessible by a number of different characterization methods and at the same time exhibit good stability and variability. The aim of this work is to design and prepare a microfluidic chip on which a planar lipid bilayer can be prepared. It therefore presents microfluidic device prepared by soft lithography of PDMS adapted for model membrane formation by self-assembly of phospholipids at the interface of aqueous and organic phases created by the architecture of the microfluidic device. Formation of the model membrane was visualized by optical microscopy and fluorescence-lifetime imaging microscopy.

Kiddie-SADS Reveals High Rates of DSM-IV Disorders in Children and Adolescents with Autism Spectrum Disorders

Prevalence of current comorbid DSM-IV disorders was assessed in a special school population of children and adolescents with ASD (N = 71, age 6.0–17.9 years), representing all cognitive levels and main ASD subgroups. Symptoms were assessed through parent interview and association to child characteristics was explored. Seventy-two percent was diagnosed with at least one comorbid disorder. Anxiety disorders (41%) and attention deficit/hyperactivity disorder (31%) were most prevalent. Obsessive–compulsive disorder was more common in older children, and oppositional defiant disorder/conduct disorder more prevalent in pervasive developmental disorder, not otherwise specified. Our results show high rates of comorbid DSM-IV disorders and underscore the importance of such evaluation in children ASD. However, diagnostic challenges are present and future research on the diagnostic validity of comorbid psychiatric disorders is needed

Mellom barken og veden ... En praxeologisk studie av norske fastlegers helsevurdering i førerkortsaker.

Sammendrag Masteroppgavens tittel er: Mellom barken og veden … En praxeologisk studie av norske fastlegers helsevurdering i førerkortsaker. Mitt utgangspunkt er de nye helsekravene til førerkort som trådte i kraft 01.10.2016. Med disse kravene fikk fastlegene ansvaret for å vurdere om pasientene er i helsemessig stand til å kjøre trafikksikkert ved bruk av legemiddelassistert behandling med benzo-preparater. Fastlegene fikk dermed en todelt rolle i møte med pasientene, de er både behandlere og sakkyndige. Det fikk meg til å undre meg over hvordan håndterer fastlegene det motsigelsesfylte oppdraget de har overfor pasienter som bruker benzo-preparater. Utfordrer denne motsetningen i deres oppgave relasjonen mellom pasient og lege, og hvilke strategier benytter legene i møte med pasientene? Formålet med oppgaven er å frembringe kunnskap som kan bidra til å forklare og forstå vurderingspraktikken hos fastlegen, og i hvilken grad denne kan bidra til at den enkelte bruker av benzo-preparater får hjelp til å vurdere sin kjøreevne i samsvar med lovverket som legger ansvaret for å gjøre denne vurderingen hos sjåføren. Fastlegen har likevel et ansvar for å følge opp medikamentbruken og vurdere om den er forenlig med bilkjøring hos pasienter som har førerkort, samtidig som de har andre omsorgsoppgaver overfor pasientene. Undringen rundt temaet har ledet frem til forskningsspørsmålet: Hvordan håndterer fastlegene det motsigelsesfylte oppdraget de har overfor pasienter som bruker benzo-preparater? Forskningsspørsmålet sikter seg inn på å beskrive praktikkene med henblikk på å forklare og forstå hvilke subjektive faktorer (disposisjoner og posisjoneringer) ved fastlegenes bakgrunn, fastlegenes sosiale posisjon og objektive faktorer ved deres virksomhet, som faglige retningslinjer og samfunnsstrukturer, som påvirker vurderingspraktikken deres. Studien anvender en praxeologisk optikk og jeg bruker Bourdieus teoretiske begreper habitus, felt, sosialt rom og doxa som analytiske verktøy. Det empiriske jeg analyserer for å kunne besvare forskningsspørsmålet er hentet fra intervju med seks fastleger mellom 35-62 år, samt dokumenter om fastlegeordningen, stortingsmeldinger og lovverk som regulerer bruk av kjøretøy. I studien kommer det frem at flere faktorer, både subjektive og objektive, kan være medvirkende betingelser for fastlegenes vurderingspraktikk. Det viser seg i intervjuene at legene opplever behandling med benzo-preparater som svært utfordrende både for lege-pasientforholdet og kapasiteten i en travel hverdag, og resultatet blir ofte langvarige foreskrivninger av benzo-preparater. Fastlegefeltets doxa, «pasientsentrert medisin» der pasientene selv er deltagende i egen behandling, fremstår offisielt som ønsket, men i det empiriske materialet er denne typen praksis fraværende. Derimot fremstår den juridiske stemmen, helsekravene i førerkortforskriften, som sterk og strukturerende, og den later til å være styrende for legenes praktikk. Helsekravene i forskriften fremgår som et forhandlingskort der agentene bruker kravene som en motivasjon og regulering av forbruket av benzodiazepiner.SYKD395MAMD-HELSEMAMD-SY

Raman Microspectroscopic Analysis of Selenium Bioaccumulation by Green Alga Chlorella vulgaris

Selenium (Se) is an element with many commercial applications as well as an essential micronutrient. Dietary Se has antioxidant properties and it is known to play a role in cancer prevention. However, the general population often suffers from Se deficiency. Green algae, such as Chlorella vulgaris, cultivated in Se-enriched environment may be used as a food supplement to provide adequate levels of Se. We used Raman microspectroscopy (RS) for fast, reliable, and non-destructive measurement of Se concentration in living algal cells. We employed inductively coupled plasma-mass spectrometry as a reference method to RS and we found a substantial correlation between the Raman signal intensity at 252 cm(-1) and total Se concentration in the studied cells. We used RS to assess the uptake of Se by living and inactivated algae and demonstrated the necessity of active cellular transport for Se accumulation. Additionally, we observed the intracellular Se being transformed into an insoluble elemental form, which we further supported by the energy-dispersive X-ray spectroscopy imaging

Inertial effects on thin-film wave structures with imposed surface shear on an inclined plane

This study provides an extended approach to the mathematical simulation of thin-film flow on a flat inclined plane relevant to flows subject to high surface shear. Motivated by modelling thin-film structures within an industrial context, wave structures are investigated for flows with moderate inertial effects and small film depth aspect ratio, epsilon. Approximations are made assuming a Reynolds number, Re ~ O(1/epsilon), and depth-averaging used to simplify the governing Navier-Stokes equations. A parallel Stokes flow is expected in the absence of any wave disturbance and a generalisation for the flow is based on a local quadratic profile. This approach provides a more general system which includes inertial effects and is solved numerically. Flow structures are compared with studies for Stokes flow in the limit of negligible inertial effects. Both two-tier and three-tier wave disturbances are used to study film profile evolution. A parametric study is provided for wave disturbances with increasing film Reynolds number. An evaluation of standing wave and transient film profiles is undertaken and identifies new profiles not previously predicted when inertial effects are neglected

Tsunami response in semienclosed tidal basins using an aggregated model

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of American Society of Civil Engineers for personal use, not for redistribution. The definitive version was published in Journal of Hydraulic Engineering 138 (2012): 744–751, doi:10.1061/(ASCE)HY.1943-7900.0000573.An aggregated model to evaluate tsunami response in semi-enclosed water bodies is presented in this work. The model is based on one-dimensional shallow water equations and can include long-wave external forcing such as a tsunami. It has been successfully validated against experimental data from a physical model, and its predictions for a case study have been compared with results from the COMCOT numerical model. The model can be used as a predictive tool because a calibration using a theoretical value for expansion and contraction losses has been performed, and differences with the typical calibration are less than 10% which is considered acceptable. This allows using the model in the absence of measured data, which is very difficult to obtain in case of a tsunami event. A case study for the Gulf of Cádiz (Spain) has been simulated with the COMCOT model. The aggregated model predicted the response for a harbor more accurately than for estuarine systems with tidal flats. Nevertheless, the aggregated model has been demonstrated as a useful general tool to predict the response of semi-enclosed tidal basins to a tsunami event, and hybrid models coupling advanced models to simulate ocean tsunami propagation with the model presented here would be useful in developing coastal warning alert systems

Utility of the Child Behavior Checklist as a Screener for Autism Spectrum Disorder

The Child Behavior Checklist (CBCL) has been proposed for screening of autism spectrum disorders (ASD) in clinical settings. Given the already widespread use of the CBCL, this could have great implications for clinical practice. This study examined the utility of CBCL profiles in differentiating children with ASD from children with other clinical disorders. Participants were 226 children with ASD and 163 children with attention-deficit/hyperactivity disorder, intellectual disability, language disorders, or emotional disorders, aged 2–13 years. Diagnosis was based on comprehensive clinical evaluation including well-validated diagnostic instruments for ASD and cognitive testing. Discriminative validity of CBCL profiles proposed for ASD screening was examined with area under the curve (AUC) scores, sensitivity, and specificity. The CBCL profiles showed low discriminative accuracy for ASD (AUC 0.59–0.70). Meeting cutoffs proposed for ASD was associated with general emotional/behavioral problems (EBP; mood problems/aggressive behavior), both in children with and without ASD. Cutoff adjustment depending on EBP-level was associated with improved discriminative accuracy for school-age children. However, the rate of false positives remained high in children with clinical levels of EBP. The results indicate that use of the CBCL profiles for ASD-specific screening would likely result in a large number of misclassifications. Although taking EBP-level into account was associated with improved discriminative accuracy for ASD, acceptable specificity could only be achieved for school-age children with below clinical levels of EBP. Further research should explore the potential of using the EBP adjustment strategy to improve the screening efficiency of other more ASD-specific instruments

Eddy formation behind the tropical island of Aldabra

Oceanic eddy formation behind the tropical island of Aldabra is examined with a one-layer reduced gravity model. Thresholds for flow separation, eddy formation, eddy shedding, and wake instabilities are determined and compared with theory, observations and results of laboratory experiments for both rotating and non-rotating flows. It is shown that non-rotating fluid theory and the Reynolds number are appropriate for describing the occurrence of eddy shedding. For islands at higher lalitudes, thresholds move nearer those found in rotating laboratory experiments Strouhal numbers calculated from the model results agree with those predicted theoretically, confirming that the frequency of eddy shedding does not increase indefinitely with Reynolds number. Both the model results and data from the CZCS archive suggest that eddy shedding and the associated enhanced biological activity (and thus CO2 uptake) are common phenomena for Aldabra and by implication, other oceanic islands

Comparisons of the factor structure and measurement invariance of the Spence children’s anxiety scale - parent version in children with autism spectrum disorder and typically developing anxious children

The Spence Children’s Anxiety Scale - Parent version (SCAS-P) is often used to assess anxiety in children with autism spectrum disorder (ASD), however, little is known about the validity of the tool in this population. The aim of this study was to determine whether the SCAS-P has the same factorial validity in a sample of young people with ASD (n=285), compared to a sample of typically developing young people with anxiety disorders (n=224). Poor model fit with all of the six hypothesised models precluded invariance testing. Exploratory factor analysis indicated that different anxiety phenomenology characterises the two samples. The findings suggest that cross-group comparisons between ASD and anxious samples based on the SCAS-P scores may not always be appropriat