Temperature dependent transport behavior of n-InN nanodot/p-Si heterojunction structures

The present work explores the temperature dependent transport behavior of n-InN nanodot/p-Si(100) heterojunction diodes. InN nanodot (ND) structures were grown on a 20 nm InN buffer layer on p-Si(100) substrates. These dots were found to be single crystalline and grown along 001] direction. The junction between these two materials exhibits a strong rectifying behavior at low temperatures. The average barrier height (BH) was determined to be 0.7 eV from current-voltage-temperature, capacitance-voltage, and flat band considerations. The band offsets derived from built-in potential were found to be Delta E-C=1.8 eV and Delta E-V=1.3 eV and are in close agreement with Anderson's model. (C) 2010 American Institute of Physics. doi:10.1063/1.3517489]

Blivande socionomers svar på ett yrkesetiskt dilemma - Hur klienten bemöts och hur dilemmat löses

Syftet med denna studie är att genom data-analys triangulation undersöka socionomstuderandes svar på ett yrkesetiskt dilemma av omsorgsetisk natur. Samplet består av 32 socionomer i början av sina studier som har svarat på ett hypotetiskt dilemma om hur de skulle bemöta en ung kvinna som ber om råd i en mycket svår situation. De huvudsakliga teoretiska utgångspunkterna för detta arbete är ECI (Ethic of Care Interview) som utvecklats av Eva Skoe som metod för att undersöka omsorgsetik, samt Osers och Althofs teori om diskursiva problemlösningsmetoder bland professionella. Som grundläggande teorier för all modern forskning om människans moralutveckling, presenteras också Carol Gilligans och Lawrence Kohlbergs teorier samt den huvudsakliga kritiken dessa bemött. Carol Gilligan är den som ursprungligen presenterade tanken om att det finns två olika typer av moraliskt tänkande där omsorgsetik är mer typisk för kvinnor och rättviseetik är mer typisk för män. Den första delen av analysen är en innehållsanalys där svaren på det yrkesrelaterade dilemmat på olika ECI stadium jämförs med varandra. Poängsättningen i ECI har varit grunden för denna analys. Den andra delen av analysen är en deduktiv teoribunden analys, där jag undersökt i fall Osers och Althofs modell om problemlösningsstrategier även går att tillämpa på ett yrkesetiskt dilemma. Slutligen tar jag också ställning till dessa två teoriers kompatibilitet. Resultatet visar att eleverna har svarat aningen sämre på det yrkesetiska dilemmat än vad deras allmänna ECI stadium är. Detta kan bero på att de är i början av sina studier men också på det allmänna klimat som råder inom socialbranschen. Teorin om diskursiva problemlösningsstrategier går inte heller att tillämpa på detta yrkesetiska dilemma, eftersom den hypotetiska klientens självbestämmanderätt gör en diskursiv lösning omöjlig. Till följd av detta har jag skapat en ny modell som baserar sig på 6 kategorier utgående från de faktorer de intervjuade lyfter fram som de viktigaste i den professionellas möte med klienten. Eftersom den nya modellen inte är hierarkisk, kan de två teorierna inte jämföras med varandra på så sätt att högre ECI nivå skulle innebära en viss typ av problemlösningsstrategi.

pi.-Facial selectivities in cycloadditions to norbornyl- and norbornenyl-fused p-benzoquinones

The stereochemistry of the Diels-Alder cycloaddition of several dienes to the facially perturbed dienophiles 2,3-norbornenobenzoquinone (3) and 2,3-norbornanobenzoquinone (4) has been examined. Unambiguous structural proof for the adducts formed has been obtained from complementary 'H and I3C NMR spectral data and in two cases through X-ray crystal structure determination. While 1,3-~yclopentadiene1, ,3-~yclohexadienea, nd cyclooctatetraene exhibit preference for addition to 3 from the bottom side, the stereochemical outcome is reversed in their response to 4.1,3-DiphenyIisobenzofuran and 1,2,3,4-tetrachloro-5,5-dimethoxycyclopentadieenneg aged 3 from the top side with marked selectivity, which is further enhanced in their reaction with 4. The observed stereoselectivities seem to be essentially controlled by steric interactons at the transition state. Model calculations provide support for this interpretation.

Microsomal redox systems in brown adipose tissue: high lipid peroxidation, low cholesterol biosynthesis and no detectable cytochrome P-450

The presence of redox systems in microsomes of brown adipose tissue (BAT) in cold exposed rats was investigated and compared with liver. BAT microsomes showed high activity of lipid peroxidation measured both by the formation of malondialdehyde (MDA) and by oxygen uptake. NADH and NADPH dependent cytochrome c reductase activity were present in both BAT and liver microsomes. Aminopyrine demethylase and aniline hydroxylase activities, the characteristic detoxification enzymes in liver microsomes could not be detected in BAT microsomes. BAT minces showed very poor incorporation of [1-14C]acetate and [2-14C]-mevalonate in unsaponifiable lipid fraction compared to liver. Biosynthesis of cholesterol and ubiquinone, but not fatty acids, and the activity of 3-hydroxy-3-methyl glutaryl CoA reductase appear to be very low in BAT. Examination of difference spectra showed the presence of only cytochrome b 5 in BAT microsomes. In addition to the inability to detect the enzyme activities dependent on cytochrome P-450, a protein with the characteristic spectrum, molecular size in SDS-PAGE and interaction with antibodies in double diffusion test, also could not be detected in BAT microsomes. The high activity of lipid peroxidation in microsomes, being associated with large oxygen uptake and oxidation of NADPH, will also contribute to the energy dissipation as heat in BAT, considered important in thermogenesis.

Arene ruthenium complexes of N,N′- and N,O-donor schiff base ligands: an X-ray structure of [(η6-p-cymene) RuCl(C5,H4N-2-CH=NC6H4-p-Me)Cl·C6H6·H2O

Arene ruthenium(II) Schiff base complexes of formulations [(η -p-cymene)RuCl(C5H4N-2-CH=NC6H4-p-X)](ClO4) (1) and [(η6-p-cymene)RuCl(O-o-C6H4CH=NC6H4-p-X)] (2) (X = H, Me, OMe, NO2, Cl) were prepared by reacting [(η6-p-cymene)RuCl2]2 with corresponding pyridine-2-carboxaldimines and sodium salts of salicylaldimines in dry THF, respectively. Complex 1 is isolated as a perchlorate salt. The molecular structure of [(η6-p-cymene)RuCl(C5H4 N-2-CH=NC6H4-p-Me)]Cl·C6H6·H2O has been determined by X-ray crystallography. The complex contains an η6-p-cymene group, a chloride and a bidentate chelating Schiff base ligand.

Dexamethasone negatively regulates phenobarbitone-activated transcription but synergistically enhances cytoplasmic levels of cytochrome P-450b/e messenger RNA

Dexamethasone has a potentiating effect on phenobarbitone mediated induction of cytochrome P-450b + e mRNAs in adult rat liver. However, the glucocorticoid inhibits phenobarbitone-activated transcription of cytochrome P-450b + e mRNAs by 60-70%. This inhibitory effect is evident in run-off transcription of the endogenous genes as well as in the transcription of an added cloned gene fragment. Dexamethasone inhibits the phenobarbitone-mediated increase in the binding of a transcription factor(s) to the upstream region of the gene as evidenced by gel retardation and Southwestern blot analysis. The glucocorticoid does not stabilize the phenobarbitone-induced polyribosomal cytochrome P-450b + e mRNAs but appears to stabilize the nuclear transcripts. It is proposed that a negative element may mediate the action of dexamethasone at the level of nuclear transcription and stabilization of the nuclear transcript may account for the potentiating effect of the glucocorticoid on phenobarbitone-mediated increase in cytochrome P-450b + e mRNAs in the cytoplasm of the adult rat liver. However, the cytochrome P-450b protein levels are slightly lower in phenobarbitone + dexamethasone treatment than in phenobarbitone-treated liver microsomes.

Developmental regulation of cytochrome P-450 (b+e) and glutathione transferase (Ya+Yc) gene expression in rat liver

The expression of cytochrome P-450 (b+e) and glutathione transferase (Ya+Yc) genes has been studied as a function of development in rat liver. The levels of cytochrome P-450 (b+e) mRNAs and their transcription rates are too low for detection in the 19-day old fetal liver before or after phenobarbitone treatment. However, glutathione transferase (Ya+Yc) mRNAs can be detected in the fetal liver as well as their induction after phenobarbitone treatment can be demonstrated. These mRNAs contents as well as their inducibility with phenobarbitone are lower in maternal liver than that of adult nonpregnant female rat liver. Steroid hormone administration to immature rats blocks substantially the phenobarbitone mediated induction of the two mRNA families as well as their transcription. It is suggested that steroid hormones constitute one of the factors responsible for the repression of the cytochrome P-450 (b+e) and glutathione transferase (Ya+Yc) genes in fetal liver.

Elewård på finska och pä svenska. En fallstudie som granskar samband mellan socialt kap språk och ungdomars välmående

Forskningen utreder skillnader mellan finsk- och svenskspråkiga skolor i en kommun i Nylands län utgående från elevvårdens synvinkel. Syftet är att kartlägga situationen i en kommun och synliggöra de skillnader och faktorer som påverkar det sociala kapitalets mängd i skolorna. Skillnaderna betraktas utgående från det sociala kapitalets inverkan på gemenskapen och från ekologisk synvinkel. Sambandet mellan det sociala stöd och den sociala kontroll som särskilt de vuxna i skolan producerar, har betydelse för skolelevers välmående. För att kunna bilda en socialt stödande och socialt kontrollerande atmosfär krävs det funktionella förändringar i skolan. Särskilt de vuxna i skolan skulle behöva mera gemenskap. Elevvårdsarbetet och skolarbetet riktar sig främst mot elever i dag, fastän de vuxna skulle behöva stärka sina sociala förhållanden. Bris i uppkomsten av socialt stöd och kontroll beror främst på problem i samarbete och kommunikation mellan de vuxna i skolan. Skolkuratorerna är de enda professionella inom skolan som i sitt arbete tar hela skolan som gemenskap i beaktande. Denna forskning är en abduktiv kvalitativ fallstudie som är tili sin karaktär beskrivande. Som data används intervjuer av elevvärdspersonalen i kommunen och enkäten Hälsa i skolan av Institutet för hälsa och välfärd från år 2008. Viktigaste källan för forskningen är Noora Ellone (2008) forskning "Kasvuyhteisö nuoren turvana".

Literature Review: Investigating Drug Transport at the Blood-Brain Barrier and the Effects of P-glycoprotein on the Brain Distribution of Drugs.

The blood-brain barrier (BBB) is a unique barrier that strictly regulates the entry of endogenous substrates and xenobiotics into the brain. This is due to its tight junctions and the array of transporters and metabolic enzymes that are expressed. The determination of brain concentrations in vivo is difficult, laborious and expensive which means that there is interest in developing predictive tools of brain distribution. Predicting brain concentrations is important even in early drug development to ensure efficacy of central nervous system (CNS) targeted drugs and safety of non-CNS drugs. The literature review covers the most common current in vitro, in vivo and in silico methods of studying transport into the brain, concentrating on transporter effects. The consequences of efflux mediated by p-glycoprotein, the most widely characterized transporter expressed at the BBB, is also discussed. The aim of the experimental study was to build a pharmacokinetic (PK) model to describe p-glycoprotein substrate drug concentrations in the brain using commonly measured in vivo parameters of brain distribution. The possibility of replacing in vivo parameter values with their in vitro counterparts was also studied. All data for the study was taken from the literature. A simple 2-compartment PK model was built using the Stella™ software. Brain concentrations of morphine, loperamide and quinidine were simulated and compared with published studies. Correlation of in vitro measured efflux ratio (ER) from different studies was evaluated in addition to studying correlation between in vitro and in vivo measured ER. A Stella™ model was also constructed to simulate an in vitro transcellular monolayer experiment, to study the sensitivity of measured ER to changes in passive permeability and Michaelis-Menten kinetic parameter values. Interspecies differences in rats and mice were investigated with regards to brain permeability and drug binding in brain tissue. Although the PK brain model was able to capture the concentration-time profiles for all 3 compounds in both brain and plasma and performed fairly well for morphine, for quinidine it underestimated and for loperamide it overestimated brain concentrations. Because the ratio of concentrations in brain and blood is dependent on the ER, it is suggested that the variable values cited for this parameter and its inaccuracy could be one explanation for the failure of predictions. Validation of the model with more compounds is needed to draw further conclusions. In vitro ER showed variable correlation between studies, indicating variability due to experimental factors such as test concentration, but overall differences were small. Good correlation between in vitro and in vivo ER at low concentrations supports the possibility of using of in vitro ER in the PK model. The in vitro simulation illustrated that in the simulation setting, efflux is significant only with low passive permeability, which highlights the fact that the cell model used to measure ER must have low enough paracellular permeability to correctly mimic the in vivo situation.

Coupled substitution of niobium and silicon in potassium titanyl phosphate and arsenate (KTiOPO4 and KTiOAsO4. Synthesis and nonlinear optical properties of KTi1-xNbxOX1-xSixO4 (X = P, As)

Coupled substitution of Nb(V) and Si(IV) for Ti(IV) and P(V)/As(V) in KTiOP04 (KTP) and KTiOAsO4 (KTA) giving new series of nonlinear optical materials, KTi1-xNbxOX1-xSixO4 (X=P,As), has been investigated. Substitution up to x = 0.40 readily occurs, the members retaining the orthorhombic (Pna2(1)) structure of KTP. The second harmonic generation (SHG) property of the parent KTP and KTA is not adversely affected by the coupled substitution. SHG intensity of the powder samples of the X = P series shows a slight increase with x up to x = 0.15; for 0.15 < x less-than-or-equal-to 0.40, there is a decrease in SHG intensity as compared to that for KTP. A similar trend in SHG intensity is seen for the arsenic analogs.