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Många elever på yrkesintroduktion når inte kunskapskraven i svenska som andraspråk, åk 9. För att nyansera bedömningen görs en inplacering i nivåmodellen enligt processbarhetsteorin. För att studera nivån undersöks verbfrasens betydelse i 8 elevtexter från introduktionsprogrammet yrkesintroduktion. Resultatet visar att flera elever processar på nivå 4 och 5 inom processbarhetsteorin och det är möjligt att en del elevtexter ses som mer avancerade och därför närmare godkänt. I uppsatsen hävdas att en bedömning enligt processbarhetsteorin kan visa en ’second opinion’ i vilken elever som använder mer avancerade grammatiska strukturer ligger närmare ett godkänt betyg. Om detta räcker för ett godkänt betyg måste dock avgöras från fall till fall. I uppsatsen diskuteras därför bedömning utifrån nyanser och konsekvenser som en användning av processbarhetsteorins modell kan utgöra. / <p>Svenska som andraspråk</p>

Magister Educationis - MEd / Schools played an important role during apartheid in shaping the mindsets of learners. In contemporary South Africa schools can now play a similar role in promoting democratic values in order to build a more just, humane and democratic society in a democratic South Africa. Through democratic citizenship, democratic schools can be created. Apple and Beane (1999, p. 10) state that democratic schools are the result of specific attempts by educators to put arrangements in place that will bring democracy to life. These arrangements and opportunities involve the production of democratic structures and processes through which life in a school is carried out and the creation of a curriculum that will allow young people the opportunity to experience the nature of democracy.

Type 1 Diabetes (T1D) is an autoimmune disease characterized by islet -specific T cells that infiltrate the pancreas and destroy the β-cells, crippling the necessary supply of insulin to control blood glucose levels. Although the disease can be managed by blood glucose monitoring, insulin injections and strict dietary regimens, there is currently no cure and complications continue to cause significant morbidity and mortality. Immunotherapies designed to inhibit islet-specific T cells are an attractive approach to treat T1D. Antibodies blocking the Interleukin-7/Interleukin-7 Receptor α (IL-7/IL-7Rα) pathway, which is critical for naïve and memory T cell survival, have shown promise in the non-obese diabetic (NOD) mouse model. Systemic administration of anti-IL-7Rα antibodies have prevented and reversed T1D in these models. However, hyperglycemia returned upon cessation of treatment, indicating no durable tolerance was established. Because of these results, I sought to better understand the mechanisms underlying the impact of IL-7Rα blockade on conventional islet-specific T cells and regulatory T cells (Tregs). I hypothesized that IL-7 signaling blockade (1) altered metabolism leading to impaired diabetogenic T cell effector functions and (2) impaired Tregs in peripheral tissues, potentially diminishing the therapeutic activity of anti-IL-7Rα antibodies. The data show that IL-7 signaling blockade impaired mitochondrial respiration independent of calcium signaling and downstream proteins. Impaired respiration shifted T cells to a more inefficient metabolic state. These inefficiencies were associated with diminished pro-inflammatory cytokine production. The cell-intrinsic role of IL-7 signaling in Tregs was assessed by crossing floxed IL-7Rα NOD mice with NOD mice that expressed Cre recombinase exclusively in Foxp3+ Tregs. At the onset of T1D IL-7Rα-deficient Tregs presented in lower frequencies than IL-7Rα-sufficient Tregs in pancreatic lymph nodes, and expressed higher levels of the co-inhibitory receptors PD-1 and TIGIT, indicating a more exhausted phenotype. Importantly, NOD mice with IL-7Rα-deficient Tregs developed T1D earlier. The data presented herein show that IL-7 signaling regulates T cell mitochondrial metabolism, T cell effector function, and identifies a role for IL-7 in the survival and function of Tregs in peripheral tissues during T1D development. This work simultaneously validates the IL-7 pathway as a potential immunotherapeutic target to modulate islet-specific T cells and cautions that unintended effects on protective Tregs must be taken into account for therapeutic strategies.

The ontogenic destruction of dopamine (DA) neurons in rat brain is associated with supersensitization of DA D1 receptors. This effect is attenuated when rats are cotreated in ontogeny with the serotonin (5-HT) neurotoxin, 5,7-dihydroxytryptamine (5,7-DHT). In an attempt to determine whether 5-HT fibers might have a similar modulatory role on the sensitivity of the DA D2 receptor complex, we pretreated rats with desipramine HCl (20 mg/kg IP, base), 1 h before the DA neurotoxin, 6-hydroxydopamine (6-OHDA; 134 μg ICV, base) and/or 5,7-DHT (75 μg ICV) and/or vehicle. At about 3 months after birth dose-effect curves for quinpirole-induced oral activity were constructed for each group of rats. We found that quinpirole, an agonist for the DA D2 receptor complex, produced a dose-related increase in oral activity in all groups of rats. After a 200 μg/kg dose of quinpirole HCl, however, neonatal 5,7-DHT-lesioned rats had a peak oral response of 54.4 ± 5.1 (mean and SEM) vs. 22.6 ± 4.8 for control rats (p < 0.01). In neonatal 6-OHDA-lesioned rats this dose of quinpirole increased oral activity to 36.8 ± 5.8 oral movements (p < 0.05 vs. control). In rats lesioned with both 5,7-DHT and 6-OHDA, the oral response was not different from control. The enhanced oral response to quinpirole in 5,7-DHT-lesioned rats was attenuated by spiperone, an antagonist for the DA D2 receptor complex. These findings are believed to be the first to demonstrate that receptors of the DA D2 complex become sensitized after ontogenic injury to 5-HT fibers. This effect is opposite to the attenuated sensitivity of DA D1 receptors in rats with a similar 5-HT lesion.

Angiotensin-(1-7) (Ang-(1-7)) is reported to be equipotent with angiotensin II (AII) in producing some central biological effects but the receptors responsible for these actions have not been defined. Three classes of receptor have been proposed: AT1, AT2, and a putative Ang-(1-7) selective receptor. This study specifically evaluates Ang-(1-7) competition at AII binding sites (AT1 and AT2) in the rat brain. 125I Sar1 Ile8 AII (269-312 pM) was used to conduct receptor autoradiographic binding assays in brain sections. Competition with Ile5 AII and Val5 AII was similar at nuclei in which either AT1 or AT2 receptor subtypes predominate (Ki = 11-18 nM). Ang-(1-7) competed 150-fold less effectively than native AII at AT1 predominant brain nuclei (Ki = 2.4 μM). At brain regions where AT2 receptors predominate, Ang-(1-7) showed a very low affinity (Ki = 104 μM) for the majority of the 125I Sar1 Ile8 AII binding sites (AT2). A small proportion of 125I Sar1 Ile3 AII binding sites showed an affinity of 2.0 μM, presumably AT1 receptors present in those brain regions. For biological responses where Ang-(1-7) is reported to be equipotent with AII, it is unlikely that these actions are mediated by the widely distributed AT1 or AT2 receptor subtypes which recognize 125I Sar1 Ile8 AII.

Dopamine (DA) neurons are implicated in the hyperlocomotion of neonatal 6-hydroxydopamine (6-OHDA)-lesioned rats, an animal model of attention deficit hyperactivity disorder (ADHD). Because serotonin (5-HT) neurons mediate some DA agonist effects, we investigated the possible role of 5-HT neurons on locomotor activity. Rats were treated at 3 days after birth with vehicle or 6-OHDA (134 μg ICV; desipramine pretreatment, 20 mg/kg IP, 1 h), and at 10 weeks with vehicle or 5,7-dihydroxytryptamine (5,7-DHT; 75 μg ICV; pretreatment with desipramine and pargyline, 75 mg/kg IP, 30 min), to destroy DA and/or 5-HT fibers. Intense spontaneous hyperlocomotor activity was produced in rats lesioned with both 6-OHDA and 5,7-DHT. Locomotor time in this group was 550 ± 17 s in a 600 s session, vs. 127 ± 13 s in the 6-OHDA group and <75 s in 5,7-DHT and intact control groups (p < 0.001). Oral activity dose-effect curves established that 5,7-DHT attenuated DA D1 receptor supersensitivity and further sensitized 5-HT2c receptors. Acute treatment with dextroamphetamine (0.25 mg/kg SC) reduced locomotor time in 6-OHDA+5,7-DHT-lesioned rats to 76 ± 37 s (p < 0.001). Striatal DA was reduced by 99% and 5-HT was reduced by 30% (vs. 6-OHDA group). Because combined 6-OHDA (to neonates) and 5,7-DHT (to adults) lesions produce intense hyperlocomotion that is attenuated by amphetamine, we propose this as a new animal model of ADHD. The findings suggest that hyperactivity in ADHD may be due to injury or impairment of both DA and 5-HT neurons.

Comparison of the observed and calculated vibrational frequencies of all-trans-octatetraene indicates that the density functional theory (DFT) using Becke's exchange and Lee-Yang-Parr's correlation functionals is as accurate as the Hartree-Fock (HF)-based scaled quantum mechanical force field approach in predicting fundamental vibrational frequencies. As the DFT calculation does not use any empirical parameters pertaining to the subject molecule and its computational cost scales more favorably than that of the HF theory, it is a more promising approach to molecular vibrational problems and should replace the empirical normal coordinate analysis for assisting vibrational assignments.

Grooming behavior in rats has so far been known to be induced mainly by dopamine agonists type D1. In order to explore the involvement of serotonine (5-HT) and its receptors in such a behavior, rats were exposed to two phases of treatment: to the serotonin neurotoxin 5,7-dihydroxytryptamine (5,7-DHT), injected intraventricularly three days after birth, and to the serotonin partial agonist m-chlorophenylpiperazine (mCPP), administered in two dose levels, two months later. Grooming behavior was monitored immediately before and after the higher dose of mCPP, while brain levels of 5-HT and its major metabolite 5-HIAA were assayed one week after mCPP administration. It is documented that while a low dose of mCPP in the non-lesioned rats increased the grooming-time by 5.7-fold, the higher mCPP dose in the non-lesioned non-primed rats increased grooming behavior by 3.6-fold. The 5,7-DHT lesions caused a 6.7-fold increase in the non-primed rats, and a 4.2-fold increase in the primed ones. These increases were noticeable only in male rats. When a higher dose of mCPP followed its lower dose in the 5,7-DHT-lesioned rats, a 3.6-fold decrease was recorded only in the female rats. A 88% and 94% drop in 5-HT and 5-HIAA levels in the brain neostriatum of the 5,7-DHT-lesioned rats was noticed in both sexes, one week after mCPP administration. These findings are the first to demonstrate that the 5-HT2 partial agonist mCPP is capable of modifying grooming behavior, and that 5,7,-DHT brain lesions increase basal grooming time, suggesting that 5-HT neurons and receptors are involved in grooming behavior in rats.

The flavone 3,5,7-trihydroxy-6-methoxyflavone was isolated from leaf extracts of Chromolaena leivensis (Hieron), commonly named plant of cancer. It was identified based on their physicochemical propierties and spectroscopic data. This compound presented a methoxylation at C6, this is uncommon in flavonoids and which may confer some specificity of its biological activity. The cytotoxic activity of this flavonoid was determined on PC3 (prostate), MDA- MB-231 (breast), HT29 (colon), SiHa (cervix) and A549 (lung) cancer cells, using MTT assay, to assess if the flavonoid contributes to the anticancer activity previously proposed for Chromolaena leivensis. The cytotoxic activity of the 3,5,7-trihydroxy-6- methoxy flavone was similar to that obtained for the flavonoid quercetin but was low compared with the positive control vincristine sulphate. The better value of the inhibitory concentration of fifty percent (IC50) 150 μ M, was achieved on SiHa cell line, while the lower activity: 4008 μ M, was obtained on HT29 cancer cell line. However, severe morphological changes were detected on cytoskeleton and nucleus of the SiHa cells detected by immunofluorescence microscopy analysis of cells exposed to the half of the IC50 concentration obtained for the flavonoid. Data indicate that the flavonoid contributes to the anticancer activity of the extracts of leaves from Chromolaena leivensis, and could broadening the spectrum of flavonoids activity against various types of cancer non hormone-dependent.