EORTC study 26041-22041: phase I/II study on concomitant and adjuvant temozolomide (TMZ) and radiotherapy (RT) with PTK787/ZK222584 (PTK/ZK) in newly diagnosed glioblastoma.

BACKGROUND: Glioblastoma is a highly vascularised tumour with a high expression of both vascular endothelial growth factor (VEGF) and VEGFR. PTK787/ZK222584 (PTK/ZK, vatalanib), a multiple VEGF receptor inhibitor, blocks the intracellular tyrosine kinase activity of all known VEGF receptors and is therefore suitable for long-term therapy of pathologic tumour neovascularisation. PATIENTS AND METHODS: The study was designed as an open-label, phase I/II study. A classic 3+3 design was selected. PTK/ZK was added to standard concomitant and adjuvant treatment, beginning in the morning of day 1 of radiotherapy (RT), and given continuously until disease progression or toxicity. PTK/ZK doses started from 500 mg with subsequent escalations to 1000 and 1250 mg/d. Adjuvant or maintenance PTK after the end of radiochemotherapy was given at a previously established dose of 750 mg twice daily continuously with TMZ at the standard adjuvant dose. RESULTS: Twenty patients were enrolled. Dose-limiting toxicities at a once daily dose of 1250 mg were grade 3 diarrhoea (n=1), grade 3 ALT increase (n=2), and myelosuppression with grade 4 thrombocytopenia and neutropenia (n=1). The recommended dose of PTK/ZK in combination with radiotherapy and temozolomide (TMZ) is 1000 mg once a day. This treatment is safe and well tolerated. CONCLUSION: In our phase I study once daily administration of up to 1000 mg of PTK/ZK in conjunction with concomitant temozolomide and radiotherapy was feasible and safe. Prolonged administration of this oral agent is manageable. The planned randomised phase II trial was discontinued right at its onset due to industry decision not to further develop this agent.

Overeducation among European university graduates : a comparative analysis ot its incidence and the importance of higher education differentiation

The incidence of over-education is here assessed by applying some standard subjective and objective indicators and a new skill-based indicator of over-education to the national samples of eight European countries in the REFLEX survey. With the exception of Spain, the results reveal that over-education is a minor risk amongst European tertiary graduates. Yet, the contrast between the standard indicators and the skill-based indicator reveals the existence of an over-education of a moderate kind in countries with high tertiary attainment rates (Norway, Finland and Netherlands). Such a type of over-education does not come to the surface when applying the standard indicators. Our results also reveal the importance of higher education differentiation (i.e. field of study and branch of higher education) for understanding the risk of over-education. Graduates from humanistic fields, bachelor courses and vocational colleges are more exposed to over-education, though their disadvantage varies across-nationally to a significant extent.

Molecular modeling of peptide-MHC class I complexes : applications to peptide based immunotherapy

Summary The specific CD8+ T cell immune response against tumors relies on the recognition by the T cell receptor (TCR) on cytotoxic T lymphocytes (CTL) of antigenic peptides bound to the class I major histocompatibility complex (MHC) molecule. Such tumor associated antigenic peptides are the focus of tumor immunotherapy with peptide vaccines. The strategy for obtaining an improved immune response often involves the design of modified tumor associated antigenic peptides. Such modifications aim at creating higher affinity and/or degradation resistant peptides and require precise structures of the peptide-MHC class I complex. In addition, the modified peptide must be cross-recognized by CTLs specific for the parental peptide, i.e. preserve the structure of the epitope. Detailed structural information on the modified peptide in complex with MHC is necessary for such predictions. In this thesis, the main focus is the development of theoretical in silico methods for prediction of both structure and cross-reactivity of peptide-MHC class I complexes. Applications of these methods in the context of immunotherapy are also presented. First, a theoretical method for structure prediction of peptide-MHC class I complexes is developed and validated. The approach is based on a molecular dynamics protocol to sample the conformational space of the peptide in its MHC environment. The sampled conformers are evaluated using conformational free energy calculations. The method, which is evaluated for its ability to reproduce 41 X-ray crystallographic structures of different peptide-MHC class I complexes, shows an overall prediction success of 83%. Importantly, in the clinically highly relevant subset of peptide-HLAA*0201 complexes, the prediction success is 100%. Based on these structure predictions, a theoretical approach for prediction of cross-reactivity is developed and validated. This method involves the generation of quantitative structure-activity relationships using three-dimensional molecular descriptors and a genetic neural network. The generated relationships are highly predictive as proved by high cross-validated correlation coefficients (0.78-0.79). Together, the here developed theoretical methods open the door for efficient rational design of improved peptides to be used in immunotherapy. Résumé La réponse immunitaire spécifique contre des tumeurs dépend de la reconnaissance par les récepteurs des cellules T CD8+ de peptides antigéniques présentés par les complexes majeurs d'histocompatibilité (CMH) de classe I. Ces peptides sont utilisés comme cible dans l'immunothérapie par vaccins peptidiques. Afin d'augmenter la réponse immunitaire, les peptides sont modifiés de façon à améliorer l'affinité et/ou la résistance à la dégradation. Ceci nécessite de connaître la structure tridimensionnelle des complexes peptide-CMH. De plus, les peptides modifiés doivent être reconnus par des cellules T spécifiques du peptide natif. La structure de l'épitope doit donc être préservée et des structures détaillées des complexes peptide-CMH sont nécessaires. Dans cette thèse, le thème central est le développement des méthodes computationnelles de prédiction des structures des complexes peptide-CMH classe I et de la reconnaissance croisée. Des applications de ces méthodes de prédiction à l'immunothérapie sont également présentées. Premièrement, une méthode théorique de prédiction des structures des complexes peptide-CMH classe I est développée et validée. Cette méthode est basée sur un échantillonnage de l'espace conformationnel du peptide dans le contexte du récepteur CMH classe I par dynamique moléculaire. Les conformations sont évaluées par leurs énergies libres conformationnelles. La méthode est validée par sa capacité à reproduire 41 structures des complexes peptide-CMH classe I obtenues par cristallographie aux rayons X. Le succès prédictif général est de 83%. Pour le sous-groupe HLA-A*0201 de complexes de grande importance pour l'immunothérapie, ce succès est de 100%. Deuxièmement, à partir de ces structures prédites in silico, une méthode théorique de prédiction de la reconnaissance croisée est développée et validée. Celle-ci consiste à générer des relations structure-activité quantitatives en utilisant des descripteurs moléculaires tridimensionnels et un réseau de neurones couplé à un algorithme génétique. Les relations générées montrent une capacité de prédiction remarquable avec des valeurs de coefficients de corrélation de validation croisée élevées (0.78-0.79). Les méthodes théoriques développées dans le cadre de cette thèse ouvrent la voie du design de vaccins peptidiques améliorés.

Interactions of Ly49 family receptors with MHC class I ligands in trans and cis.

The Ly49A NK cell receptor interacts with MHC class I (MHC-I) molecules on target cells and negatively regulates NK cell-mediated target cell lysis. We have recently shown that the MHC-I ligand-binding capacity of the Ly49A NK cell receptor is controlled by the NK cells' own MHC-I. To see whether this property was unique to Ly49A, we have investigated the binding of soluble MHC-I multimers to the Ly49 family receptors expressed in MHC-I-deficient and -sufficient C57BL/6 mice. In this study, we confirm the binding of classical MHC-I to the inhibitory Ly49A, C and I receptors, and demonstrate that detectable MHC-I binding to MHC-I-deficient NK cells is exclusively mediated by these three receptors. We did not detect significant multimer binding to stably transfected or NK cell-expressed Ly49D, E, F, G, and H receptors. Yet, we identified the more distantly related Ly49B and Ly49Q, which are not expressed by NK cells, as two novel MHC-I receptors in mice. Furthermore, we show using MHC-I-sufficient mice that the NK cells' own MHC-I significantly masks the Ly49A and Ly49C, but not the Ly49I receptor. Nevertheless, Ly49I was partly masked on transfected tumor cells, suggesting that the structure of Ly49I is compatible in principal with cis binding of MHC-I. Finally, masking of Ly49Q by cis MHC-I was minor, whereas masking of Ly49B was not detected. These data significantly extend the MHC-I specificity of Ly49 family receptors and show that the accessibility of most, but not all, MHC-I-binding Ly49 receptors is modulated by the expression of MHC-I in cis.

Regions of mouse mammary tumor virus superantigen involved in interaction with the major histocompatibility complex class II I-A molecule.

To study the major histocompatibility complex class II I-E dependence of mouse mammary tumor virus (MMTV) superantigens, we constructed hybrids between the I-E-dependent MMTV(GR) and the I-E-independent mtv-7 superantigens and tested them in vivo. Our results suggest that, although the C-terminal third mediates I-A interaction, additional binding sites are located elsewhere in the superantigen.

Fast and simple epidemiological typing of Pseudomonas aeruginosa using the double-locus sequence typing (DLST) method.

Although the molecular typing of Pseudomonas aeruginosa is important to understand the local epidemiology of this opportunistic pathogen, it remains challenging. Our aim was to develop a simple typing method based on the sequencing of two highly variable loci. Single-strand sequencing of three highly variable loci (ms172, ms217, and oprD) was performed on a collection of 282 isolates recovered between 1994 and 2007 (from patients and the environment). As expected, the resolution of each locus alone [number of types (NT) = 35-64; index of discrimination (ID) = 0.816-0.964] was lower than the combination of two loci (NT = 78-97; ID = 0.966-0.971). As each pairwise combination of loci gave similar results, we selected the most robust combination with ms172 [reverse; R] and ms217 [R] to constitute the double-locus sequence typing (DLST) scheme for P. aeruginosa. This combination gave: (i) a complete genotype for 276/282 isolates (typability of 98%), (ii) 86 different types, and (iii) an ID of 0.968. Analysis of multiple isolates from the same patients or taps showed that DLST genotypes are generally stable over a period of several months. The high typability, discriminatory power, and ease of use of the proposed DLST scheme makes it a method of choice for local epidemiological analyses of P. aeruginosa. Moreover, the possibility to give unambiguous definition of types allowed to develop an Internet database ( http://www.dlst.org ) accessible by all.

Lapatax: Safety profile of neoadjuvant lapatinib combined with docetaxel in Her 2/neu overexpressing breast cancer - EORTC protocol 10054

Objective: To assess the safety/tolerability of the combination lapatinib (L) and docetaxel (D) in patients with Her 2/neu overexpressing breast cancer (BC). This study is important as it will define how to deliver lapatinib with taxotere, a highly active drug in breast cancer. Patients and Methods: Female patients (pts) with locally advanced, inflammatory or large operable BC were treated with escalating doses of L from 1000 to 1250 mg/day, in combination with D given IV every 21 days at doses ranging from 75 to 100 mg/m2 for 4 cycles. At least 3 pts were treated at each dose level. The definition of dose limiting toxicity (DLT) is based on the toxicity assessed at cycle 1 as follows: any grade 3−4 non hematological toxicity, ANC < 0.5 G/L lasting for 7 days or more, febrile neutropenia or thrombocytopenia <25 G/L. GCSF was not permitted as primary prophylaxis. Core biopsies were mandatory at baseline and after cycle 4. Pharmcokinetic (PK) samples were collected on day 1 of cycles 1 and 2. Results: To date, 18 pts with a median age of 53 years (range 36−65) have been enrolled at 5 Dose Levels (DLs). The toxicity profile for 18 patients (68 documented cycles) is summarized below. At DL5 (1000/100), 2 pts had DLTs (neutropenia grade 4 _7 days and febrile neutropenia), and 3 additional pts were enrolled with primary prophylactic G-CSF. As expected, the safety profile improved and the dose escalation will continue with prophylactic G-CSF to investigate DL6 (1250/100). These findings are consistent with published Phase I data for this combination [1]. N= 18 patients n (%) Grade 1 Grade 2 Grade 3 Grade 4 neutropenia 1 (6) 3 (17) 13 (72) febrile neutropenia 2 (11) fatigue 8 (44) 7 (39) diarrhoea 9 (50) 3 (17) pain: joint/muscle/other 5 (28)/4 (22)/3 (17) 4 (22)/4 (22)/3 (17) 0/0/1 (6) constipation 2 (11) 3 (17) 1 (6) elevated transaminases SGPT/SGOT 7 (39)/5 (28) Conclusions: The main toxicity of the L + D combination is haematological and was reached at DL5 (1000/100), without primary GCSF. An additional DL6 with primary prophylactic GCSF is being investigated (1250/100). PK data will be presented at the meeting plus the recommended dose for phase II studies.

Lack of angiotensin I accumulation after converting enzyme blockade by enalapril or lisinopril in man.

In nine normal volunteers, a series of five venous blood samples was obtained before and up to 24 h after converting enzyme inhibition by a single oral dose of enalapril or lisinopril. Plasma renin activity and blood angiotensin I were measured. A close linear relationship was found between the increase in plasma renin activity and the increase in blood angiotensin I. The linear correlation between plasma renin activity and blood angiotensin I remained after converting enzyme inhibition. Thus, the rise in angiotensin I after inhibition of the conversion of angiotensin I to angiotensin II is due to an enhanced release of renin rather than to accumulation of angiotensin I.

Interleukin-1- and type I interferon-dependent enhanced immunogenicity of an NYVAC-HIV-1 Env-Gag-Pol-Nef vaccine vector with dual deletions of type I and type II interferon-binding proteins.

UNLABELLED: NYVAC, a highly attenuated, replication-restricted poxvirus, is a safe and immunogenic vaccine vector. Deletion of immune evasion genes from the poxvirus genome is an attractive strategy for improving the immunogenic properties of poxviruses. Using systems biology approaches, we describe herein the enhanced immunological profile of NYVAC vectors expressing the HIV-1 clade C env, gag, pol, and nef genes (NYVAC-C) with single or double deletions of genes encoding type I (ΔB19R) or type II (ΔB8R) interferon (IFN)-binding proteins. Transcriptomic analyses of human monocytes infected with NYVAC-C, NYVAC-C with the B19R deletion (NYVAC-C-ΔB19R), or NYVAC-C with B8R and B19R deletions (NYVAC-C-ΔB8RB19R) revealed a concerted upregulation of innate immune pathways (IFN-stimulated genes [ISGs]) of increasing magnitude with NYVAC-C-ΔB19R and NYVAC-C-ΔB8RB19R than with NYVAC-C. Deletion of B8R and B19R resulted in an enhanced activation of IRF3, IRF7, and STAT1 and the robust production of type I IFNs and of ISGs, whose expression was inhibited by anti-type I IFN antibodies. Interestingly, NYVAC-C-ΔB8RB19R induced the production of much higher levels of proinflammatory cytokines (tumor necrosis factor [TNF], interleukin-6 [IL-6], and IL-8) than NYVAC-C or NYVAC-C-ΔB19R as well as a strong inflammasome response (caspase-1 and IL-1β) in infected monocytes. Top network analyses showed that this broad response mediated by the deletion of B8R and B19R was organized around two upregulated gene expression nodes (TNF and IRF7). Consistent with these findings, monocytes infected with NYVAC-C-ΔB8RB19R induced a stronger type I IFN-dependent and IL-1-dependent allogeneic CD4(+) T cell response than monocytes infected with NYVAC-C or NYVAC-C-ΔB19R. Dual deletion of type I and type II IFN immune evasion genes in NYVAC markedly enhanced its immunogenic properties via its induction of the increased expression of type I IFNs and IL-1β and make it an attractive candidate HIV vaccine vector. IMPORTANCE: NYVAC is a replication-deficient poxvirus developed as a vaccine vector against HIV. NYVAC expresses several genes known to impair the host immune defenses by interfering with innate immune receptors, cytokines, or interferons. Given the crucial role played by interferons against viruses, we postulated that targeting the type I and type II decoy receptors used by poxvirus to subvert the host innate immune response would be an attractive approach to improve the immunogenicity of NYVAC vectors. Using systems biology approaches, we report that deletion of type I and type II IFN immune evasion genes in NYVAC poxvirus resulted in the robust expression of type I IFNs and interferon-stimulated genes (ISGs), a strong activation of the inflammasome, and upregulated expression of IL-1β and proinflammatory cytokines. Dual deletion of type I and type II IFN immune evasion genes in NYVAC poxvirus improves its immunogenic profile and makes it an attractive candidate HIV vaccine vector.

High Prevalence of Signs of Renal Damage Despite Normal Renal Function in a Cohort of HIV-Infected Patients: Evaluation of Associated Factors

Renal disorders are an emerging problem in HIV-infected patients. We performed a cross-sectional study of the first 1000 HIV-infected patients attended at our HIV unit who agreed to participate. We determined the frequency of renal alterations and its related risk factors. Summary statistics and logistic regression were applied. The study sample comprised 970 patients with complete data. Most were white (94%) and men (76%). Median (IQR) age was 48 (42–53) years. Hypertension was diagnosed in 19%, dyslipidemia in 27%, and diabetes mellitus in 3%. According to the Chronic Kidney Disease Epidemiology Collaboration (CKD EPI) equation, 29 patients (3%) had an eGFR < 60 ml/min/1.73m2; 18 of them (62%) presented altered albumin/creatinine and protein/creatinine (UPC or UAC) ratios. Of the patients with eGFR> 60mL/min, it was present in 293 (30%), 38 of whom (7.1%) had UPC> 300mg/g. Increased risk of renal abnormalities was correlated with hypertension (OR, 1.821 [95%CI, 1.292;2.564]; p = 0.001), age (OR, 1.015 [95%CI, 1.001;1.030], per one year; p = 0.040), and use of tenofovir disoproxil fumarate (TDF) plus protease inhibitor (PI), (OR, 1.401 [95%CI, 1.078;1.821]; p = 0.012). Current CD4 cell count was a protective factor (OR, 0.9995 [95%CI, 0.9991;0.9999], per one cell; p = 0.035). A considerable proportion of patients presented altered UPC or UAC ratios, despite having an eGFR > 60mL/min. CD4 cell count was a protective factor; age, hypertension, and use of TDF plus PIs were risk factors for renal abnormalities. Based on our results, screen of renal abnormalities should be considered in all HIV-infected patients to detect these alterations early.

“That you too were the I”: Forms of polyphonic communication in John Ashbery’s poetry

Tarkastelen tutkimuksessani amerikkalaisen John Ashberyn (1927–) runoudessa lmenevää moniäänisyyttä. Runoutta pidetään yleensä yksiäänisenä puheena, kun taas omaanin ajatellaan erityisesti Mihail Bahtinin vaikutuksesta olevan luonnostaan oniääninen kirjallisuudenlaji. Ashberyn postmoderni runous haastaa tämän äsityksen. Ashbery tunnetaan vakiintuneita runouskäsityksiä vastaan kirjoittavana avantgarde-runoilijana. Pääasiallisina tutkimuskohteinani ovat Ashberyn pitkä runoelma nimeltä ”Litany” (1979) sekä lyhyiden runojen valikoima <i>Your Name Herei> (2000). Vertailukohtana tarkastelen Ashberyn yhdessä James Schuylerin kanssa kirjoittamaa romaania <i>A Nest of Ninniesi> (1969). Teoreettisena pohjana on käytetty Ashberyä käsittelevän muun tutkimuksen lisäksi muun muassa jälkistrukturalistisiin teorioihin liittyviä ajatuksia pronominien vaikutuksesta siihen miten lukija muodostaa käsityksen subjektiivisesta läsnäolosta runossa. Ashbery käyttää persoonapronomineja ilman selkeitä viittaussuhteita. Viittaussuhteiden hämärtymisen ja fragmentaarisuuden vuoksi Ashberyn runoja pidetään usein vaikeina, eikä niistä ole helppo löytää yhtä selkeää aihetta. Hajanaisuus on kuitenkin motivoitua, koska juuri se mahdollistaa moniäänisyyden ja avoimen tekstin, joka voi sisältää monia merkityksiä. Kun runossa ei ole yhden puhujan hallitsevaa ääntä, lukijan rooli merkitysten muodostajana nousee keskeiseksi. ”Litany” on selkeästi metatekstuaalinen runo, jossa fiktiivinen taso sekoittuu runouden, taiteen ja kritiikin mahdollisuuksien pohdintaan. Runo hahmottelee uudenlaista, moniäänistä teorian ja runouden rajoja purkavaa kommunikaation muotoa. Toisen persoonan pronominien voidaan runossa usein ajatella puhuttelevan lukijaa. <i>Your Name Herei> -kokoelmassa puolestaan toisen persoonan pronominipositiot määrittyvät usein tietyiksi henkilöhahmoiksi runojen maailmassa, ja pronominipositioiden kautta runoissa rakentuu moniäänisiä dialogeja määrittymättömien henkilöhahmojen välille. Näin lukijan huomio suunnataan ensisijaisesti kommunikaation ja arkipäivän kielenkäytön kliseiden sävyihin ja asiayhteyksiin pikemminkin kuin yksittäisten lausumien sisältöön. <i>A Nest of Ninnies i>-romaani toimii näennäisestä dialogisuudestaan huolimatta ennen kaikkea yksiäänisesti, sillä romaanin yksiulotteisten henkilöhahmojen esittämiä ajatuksia hallitsee parodioimaan pyrkivä kertojanääni. Ashberyn runojen ja romaanin tarkasteleminen osoittaa, että käsitys runoudesta väistämättä yksiäänisenä ja romaanista moniäänisenä ei ole kaikilta osin ongelmaton. Moniääninen, monimerkityksinen runo voi tarjota toiselle itsenäisen aseman.

Romanssien ja runouden aikakausi. Thomas Warton keskiaikaa määrittelemässä 1750–1790

Tutkimukseni käsittelee keskiajan nousua historian tärkeäksi periodiksi 1700-luvun Englannissa näkökulmanaan Thomas Wartonin (1726–1790) kirjoitukset. Warton oli Oxfordin yliopistossa toiminut oppinut antikvaari. Wartonin pääteos <i>History of English Poetryi> (1774–1781) ei nimestään huolimatta ollut moderni kirjallisuushistoria vaan 1000–1500-luvun kirjoitettua kulttuuria laajasti käsitellyt vernakulaariin kirjallisuuteen pohjautunut esitys. Warton ja hänen lähipiiriinsä kuuluneet tutkijat tarjoavat erityisen mahdollisuuden tarkastella, miten käsitys keskiajasta omana aikakautenaanmuodostui 1700-luvun lopulla. Tutkin Wartonin ja hänen aikalaistensa toisen vuosituhannen alusta kirjoittamia arvioita Michel de Certeaun historiografisen operaation käsitteen avulla. Se koostuu kolmesta vaiheesta: Alue määrittelee sosiaaliset riippuvuussuhteet ja vaikuttimet, jotka ohjaavat tutkimusta. Käytäntö viittaa siihen, miten historioitsija valitsee materiaalinsa ja muokkaa siitä historiankirjoituksena hahmottuvan kokonaisuuden. Lopuksi kirjoitus konkreettisena ja fyysisenä ilmiönä luo illuusion lopullisuudesta ja huonosti sopivien osien yhteenkuuluvuudesta. de Certeaun teoria soveltuu paremmin vanhemman historiankirjoituksen ja oppineisuuden tarkasteluun kuin historiantutkimuksen narratiiveja analysoivat teokset, koska se kontekstualisoi laajemmin historiankirjoitukseen vaikuttavat ilmiöt. Thomas Warton ja muut 1700-luvun puolivälin oppineet määrittelivät keskiajan fiktiivisten tekstien avulla. Warton tutustui tarkasti romansseihin ja kronikoihin. Erityisen suuri merkitys keskiajan hahmottamisen kannalta oli Geoffrey Monmouthilaisen kronikalla <i> Historia regum britanniae, i> joka esitteli Englannin myyttisen varhaisen historian yhdistämällä Rooman ja oman kansallisen perinteen. Geoffreyn kronikan avulla Warton huomasi keskiaikaisten tarinoiden laajan vaikutuksen; hän kirjoitti erityisesti kuningas Arthuriin liittyneiden kertomusten merkityksestä, joka jatkui aina 1500-luvulle asti. Näin Warton löysi antiikin perinteelle haastajan keskiaikaisesta kulttuurista. Wartonin tapa esitellä keskiaikaa perustui osittain valistusajan sulavasti kirjoitetuille universaalihistorioille, osittain oppineelle luettelomaiselle esitystavalle. Käytännössä Wartonin pitkät johdantotutkielmat kuitenkin johdattavat lukijaa keskeisiin teemoihin. Niitä ovat mielikuvituksen väheneminen uusimmassa kirjallisuudessa ja toisaalta hienostuneisuuden ja tiedon kasvu. Warton ei missään vaiheessa kerro, liittyvätkö nämä teemat yhteen, mutta tulkintani mukaan ne liittyivät. Warton ajatteli kirjallisuuden menettäneen olennaisen mielikuvituksen samaan aikaan, kun yhteiskunta oli kehittynyt. Tämä auttaa hahmottamaan koko kirjallisuuden historiaa: Warton etsi alkuperäistä mielikuvitusta niin antiikin Kreikasta, Orientista kuin muinaisesta Skandinaviasta. <i>History of English Poetryi> ei pohtinut vain kirjallisuuden ja yhteiskunnan suhdetta, sillä Warton ajatteli voivansa tutkia keskiajan yhteiskuntaa kronikoiden ja romanssien avulla. Hänen käsityksensä feodalismista, hovien elämästä ja keskiaikaisista tavoista perustuivat niihin. Warton ei huomannut, että hänen käyttämänsä lähteet olivat tietoisia kirjallisia konstruktioita vaan hän piti niitä totuudenmukaisina kuvauksina. Toisaalta Wartonin tulkintaan heijastuivat myös 1700-luvun käsitykset yhteiskunnasta. Keskiajan lähteiden kuvaukset ja 1700-luvun ideaalit vaikuttivat lopulta siihen, millaiseksi populaari kuva keskiajasta kehittyi.

Influence of Insulin-like Growth Factor I (IGF-I) on the survival and the in vitro development of caprine preantral follicles

The aim of this study was to investigate the effects of the insulin-like growth factor -I (IGF-I) on survival, activation (transition from primordial to primary follicles) and growth of caprine preantral follicles cultured in vitro. Fragments of ovarian cortex were cultured for one and seven days in the absence or presence of IGF-I (0, 50 and 100ng/ml). The non-cultured and cultured tissues were processed and analyzed by histology and transmission electron microscopy. The culture for one day in a medium with 100ng/ml of IGF-I showed 86.7% of morphologically normal follicles. These results were similar (P>0.05) to the percentage of normal follicles found in the control (96.7%). It was also found that this medium increased the percentage of follicular activation (developing follicles) with one day of culture. The oocyte and follicular diameters remained similar to the control by culturing for one day in a medium containing 100ng/ml of IGF-I. The ultrastructural analysis did not confirm the integrity of the follicular fragments in a medium containing IGF-I (100ng/ml) after one and seven days of culture. In conclusion, this study demonstrated that the addition of 100 ng/ml of IGF-I in the culture medium enables the development of preantral follicles of goats with one day of culture. However, it is not sufficient to maintain the follicular integrity and the follicular survival rate after seven days of culture.

Improving the competitiveness of electrolytic Zinc process by chemical reaction engineering approach

This doctoral thesis describes the development work performed on the leachand purification sections in the electrolytic zinc plant in Kokkola to increase the efficiency in these two stages, and thus the competitiveness of the plant. Since metallic zinc is a typical bulk product, the improvement of the competitiveness of a plant was mostly an issue of decreasing unit costs. The problems in the leaching were low recovery of valuable metals from raw materials, and that the available technology offered complicated and expensive processes to overcome this problem. In the purification, the main problem was consumption of zinc powder - up to four to six times the stoichiometric demand. This reduced the capacity of the plant as this zinc is re-circulated through the electrolysis, which is the absolute bottleneck in a zinc plant. Low selectivity gave low-grade and low-value precipitates for further processing to metallic copper, cadmium, cobalt and nickel. Knowledge of the underlying chemistry was poor and process interruptions causing losses of zinc production were frequent. Studies on leaching comprised the kinetics of ferrite leaching and jarosite precipitation, as well as the stability of jarosite in acidic plant solutions. A breakthrough came with the finding that jarosite could precipitate under conditions where ferrite would leach satisfactorily. Based on this discovery, a one-step process for the treatment of ferrite was developed. In the plant, the new process almost doubled the recovery of zinc from ferrite in the same equipment as the two-step jarosite process was operated in at that time. In a later expansion of the plant, investment savings were substantial compared to other technologies available. In the solution purification, the key finding was that Co, Ni, and Cu formed specific arsenides in the “hot arsenic zinc dust” step. This was utilized for the development of a three-step purification stage based on fluidized bed technology in all three steps, i.e. removal of Cu, Co and Cd. Both precipitation rates and selectivity increased, which strongly decreased the zinc powder consumption through a substantially suppressed hydrogen gas evolution. Better selectivity improved the value of the precipitates: cadmium, which caused environmental problems in the copper smelter, was reduced from 1-3% reported normally down to 0.05 %, and a cobalt cake with 15 % Co was easily produced in laboratory experiments in the cobalt removal. The zinc powder consumption in the plant for a solution containing Cu, Co, Ni and Cd (1000, 25, 30 and 350 mg/l, respectively), was around 1.8 g/l; i.e. only 1.4 times the stoichiometric demand – or, about 60% saving in powder consumption. Two processes for direct leaching of the concentrate under atmospheric conditions were developed, one of which was implemented in the Kokkola zinc plant. Compared to the existing pressure leach technology, savings were obtained mostly in investment. The scientific basis for the most important processes and process improvements is given in the doctoral thesis. This includes mathematical modeling and thermodynamic evaluation of experimental results and hypotheses developed. Five of the processes developed in this research and development program were implemented in the plant and are still operated. Even though these processes were developed with the focus on the plant in Kokkola, they can also be implemented at low cost in most of the zinc plants globally, and have thus a great significance in the development of the electrolytic zinc process in general.

Surface characterization of chemically modified fiber, wood and paper

Inorganic-organic sol-gel hybrid coatings can be used for improving and modifying properties of wood-based materials. By selecting a proper precursor, wood can be made water repellent, decay-, moisture- or UV-resistant. However, to control the barrier properties of sol-gel coatings on wood substrates against moisture uptake and weathering, an understanding of the surface morphology and chemistry of the deposited sol-gel coatings on wood substrates is needed. Mechanical pulp is used in production of wood-containing printing papers. The physical and chemical fiber surface characteristics, as created in the chosen mechanical pulp manufacturing process, play a key role in controlling the properties of the end-use product. A detailed understanding of how process parameters influence fiber surfaces can help improving cost-effectiveness of pulp and paper production. The current work focuses on physico-chemical characterization of modified wood-based materials with surface sensitive analytical tools. The overall objectives were, through advanced microscopy and chemical analysis techniques, (i) to collect versatile information about the surface structures of Norway spruce thermomechanical pulp fiber walls and understand how they are influenced by the selected chemical treatments, and (ii) to clarify the effect of various sol-gel coatings on surface structural and chemical properties of wood-based substrates. A special emphasis was on understanding the effect of sol-gel coatings on the water repellency of modified wood and paper surfaces. In the first part of the work, effects of chemical treatment on micro- and nano-scale surface structure of 1st stage TMP latewood fibers from Norway spruce were investigated. The chemicals applied were buffered sodium oxalate and hydrochloric acid. The outer and the inner fiber wall layers of the untreated and chemically treated fibers were separately analyzed by light microscopy, atomic force microscopy and field-emission scanning electron microscopy. The selected characterization methods enabled the demonstration of the effect of different treatments on the fiber surface structure, both visually and quantitatively. The outer fiber wall areas appeared as intact bands surrounding the fiber and they were clearly rougher than areas of exposed inner fiber wall. The roughness of the outer fiber wall areas increased most in the sodium oxalate treatment. The results indicated formation of more surface pores on the exposed inner fiber wall areas than on the corresponding outer fiber wall areas as a result of the chemical treatments. The hydrochloric acid treatment seemed to increase the surface porosity of the inner wall areas. In the second part of the work, three silane-based sol-gel hybrid coatings were selected in order to improve moisture resistance of wood and paper substrates. The coatings differed from each other in terms of having different alkyl (CH3–, CH3-(CH2)7–) and fluorocarbon (CF3–) chains attached to the trialkoxysilane sol-gel precursor. The sol-gel coatings were deposited by a wet coating method, i.e. spraying or spreading by brush. The effect of solgel coatings on surface structural and chemical properties of wood-based substrates was studied by using advanced surface analyzing tools: atomic force microscopy, X-ray photoelectron spectroscopy and time-of-flight secondary ion spectroscopy. The results show that the applied sol-gel coatings, deposited as thin films or particulate coatings, have different effects on surface characteristics of wood and wood-based materials. The coating which has a long hydrocarbon chain (CH3-(CH2)7–) attached to the silane backbone (octyltriethoxysilane) produced the highest hydrophobicity for wood and wood-based materials.