32 resultados para reader-response criticism


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Human body is in continuous contact with microbes. Although many microbes are harmless or beneficial for humans, pathogenic microbes possess a threat to wellbeing. Antimicrobial protection is provided by the immune system, which can be functionally divided into two parts, namely innate and adaptive immunity. The key players of the innate immunity are phagocytic white blood cells such as neutrophils, monocytes, macrophages and dendritic cells (DCs), which constantly monitor the blood and peripheral tissues. These cells are armed for rapid activation upon microbial contact since they express a variety of microbe-recognizing receptors. Macrophages and DCs also act as antigen presenting cells (APCs) and play an important role in the development of adaptive immunity. The development of adaptive immunity requires intimate cooperation between APCs and T lymphocytes and results in microbe-specific immune responses. Moreover, adaptive immunity generates immunological memory, which rapidly and efficiently protects the host from reinfection. Properly functioning immune system requires efficient communication between cells. Cytokines are proteins, which mediate intercellular communication together with direct cell-cell contacts. Immune cells produce inflammatory cytokines rapidly following microbial contact. Inflammatory cytokines modulate the development of local immune response by binding to cell surface receptors, which results in the activation of intracellular signalling and modulates target cell gene expression. One class of inflammatory cytokines chemokines has a major role in regulating cellular traffic. Locally produced inflammatory chemokines guide the recruitment of effector cells to the site of inflammation during microbial infection. In this study two key questions were addressed. First, the ability of pathogenic and non-pathogenic Gram-positive bacteria to activate inflammatory cytokine and chemokine production in different human APCs was compared. In these studies macrophages and DCs were stimulated with pathogenic Steptococcus pyogenes or non-pathogenic Lactobacillus rhamnosus. The second aim of this thesis work was to analyze the role of pro-inflammatory cytokines in the regulation of microbe-induced chemokine production. In these studies bacteria-stimulated macrophages and influenza A virus-infected lung epithelial cells were used as model systems. The results of this study show that although macrophages and DCs share several common antimicrobial functions, these cells have significantly distinct responses against pathogenic and non-pathogenic Gram-positive bacteria. Macrophages were activated in a nearly similar fashion by pathogenic S. pyogenes and non-pathogenic L. rhamnosus. Both bacteria induced the production of similar core set of inflammatory chemokines consisting of several CC-class chemokines and CXCL8. These chemokines attract monocytes, neutrophils, dendritic cells and T cells. Thus, the results suggest that bacteria-activated macrophages efficiently recruit other effector cells to the site of inflammation. Moreover, macrophages seem to be activated by all bacteria irrespective of their pathogenicity. DCs, in contrast, were efficiently activated only by pathogenic S. pyogenes, which induced DC maturation and production of several inflammatory cytokines and chemokines. In contrast, L. rhamnosus-stimulated DCs matured only partially and, most importantly, these cells did not produce inflammatory cytokines or chemokines. L. rhamnosus-stimulated DCs had a phenotype of "semi-mature" DCs and this type of DCs have been suggested to enhance tolerogenic adaptive immune responses. Since DCs have an essential role in the development of adaptive immune response the results suggest that, in contrast to macrophages, DCs may be able to discriminate between pathogenic and non-pathogenic bacteria and thus mount appropriate inflammatory or tolerogenic adaptive immune response depending on the microbe in question. The results of this study also show that pro-inflammatory cytokines can contribute to microbe-induced chemokine production at multiple levels. S. pyogenes-induced type I interferon (IFN) was found to enhance the production of certain inflammatory chemokines in macrophages during bacterial stimulation. Thus, bacteria-induced chemokine production is regulated by direct (microbe-induced) and indirect (pro-inflammatory cytokine-induced) mechanisms during inflammation. In epithelial cells IFN- and tumor necrosis factor- (TNF-) were found to enhance the expression of PRRs and components of cellular signal transduction machinery. Pre-treatment of epithelial cells with these cytokines prior to virus infection resulted in markedly enhanced chemokine response compared to untreated cells. In conclusion, the results obtained from this study show that pro-inflammatory cytokines can enhance microbe-induced chemokine production during microbial infection by providing a positive feedback loop. In addition, pro-inflammatory cytokines can render normally low-responding cells to high chemokine producers via enhancement of microbial detection and signal transduction.

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Juvenile neuronal ceroid lipofuscinosis (JNCL) is one of the most common neurodegenerative diseases in childhood. Its clinical onset, with visual failure as the first sign, is between the ages of 4 to 8 years. During the disease progress, epilepsy, motor symptoms, cognitive decline, and psychiatric symptoms become apparent. It leads to premature death between ages 15 and 30. Treatment consists of symptomatic drug administration and various forms of rehabilitation, but to date, no curative treatment exists. To gain a more comprehensive picture of psychiatric problems, symptoms were evaluated by the Child Behavior Checklist, the Teacher Report Form, and the Children s Depression Inventory. The JNCL patients had a great number of severe psychiatric symptoms, with wide inter-individual variability. The most common symptoms were social, thought, attention, and sleep problems, somatic complaints, and aggressive behaviour. Patients with psychotropic treatment had more problems than did those without psychotropic treatment, and female patients had more problems than did males. Between 10 and 20% of the patients reported depressive symptoms. In a 5-year follow-up, [123I]β-CIT SPECT and MRI revealed a tendency of decreasing serotonin transporter (SERT) availability and progressive brain atrophy. The correlation between changes in midbrain SERT and total brain volume was positive; no correlation appeared between SERT or brain atrophy and depressive symptoms. Thus, it seems likely that the low SERT availability is associated with progressive brain atrophy; it may also predispose towards depression, however. An open survey of psychotropic drugs and their efficacy was performed on JNCL patients in Finland. The most commonly used psychotropic drugs were the antidepressant citalopram and the antipsychotic risperidone. Their efficacy was good or satisfactory in the majority of cases and they seemed well tolerated. Quetiapine had a marked effect on one patient with a history of severe psychotic symptoms. Glutamate decarboxylase 65 autoantibodies (GAD65ab), found in JNCL patients, indicate that an immunomediated reaction against GAD or GABAergic neurons may play a part in the underlying pathogenetic mechanism. GAD65ab s also appeared in the serum of all eight JNCL patients included and intermittent corticosteroid therapy was initiated in all cases. After one year, the GAD65ab s had disappeared in the two oldest patients, who experienced an improvement in motor symptoms and alertness associated with their prednisolone therapy. Two younger patients experienced a significant IQ increase, but no change in GADab s. A randomized study with longer follow-up time is needed, however, to clarify the effect of prednisolone on disease progression.

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This research analyses opinions on the system of social welfare services from the point of view of clients and the public in general in Finland. The approach is quantitative, drawing on theories of the welfare-state tradition. The data used comes from the comprehensive Welfare and Services in Finland survey compiled by STAKES. While previous research on the welfare state has predominantly focused on surveying public opinion on social protection, this research focuses on social welfare services. The main focus of this research is on publicly funded care provided by municipal social welfare services. In this research, social welfare services include child day care, services for people with disabilities, home-help services, counselling by social workers and social assistance. The research considered in particular whether the clients or the population has different opinions towards social welfare services or social benefits. In addition, the research partly covers areas of informal care provided by family and friends. The research material consisted of the STAKES Welfare and Services in Finland survey. The data was compiled in 2004 and 2006 by Statistics Finland. The research comprises five articles. Additional data have been extracted from social welfare statistics and registers. Multiple approaches were applied in the survey on welfare and services the methods in this research included interviews by phone and mail, and register data. The sample size was 5 810 people in 2004 and 5 798 in 2006. The response rates were 82.7% and 83.7%, respectively. The results indicate that a large majority (90%) of the Finnish population is of the opinion that the public sector should bear the main responsibility for organising social and health services. The system of social welfare services and its personnel have strong public support 73% and 80% respectively. However, new and even negative tones have emerged in the Finnish debate on social welfare services. Women are increasingly critical of the performance of social welfare services and the level of social protection. Furthermore, this study shows that women more often than men wish to see an increase in the amount of privately organised social welfare services. Another group critical of the performance of social welfare services are pensioners. People who had used social welfare services were more critical than those who had not used them. Thus, the severest criticism was received from the groups who use and gain most from public services and benefits. However, the education and income variables identified in earlier studies no longer formed a significant dividing line, although people with higher education tend to foster a more positive view of the performance of social welfare services as well as the level of social protection. Income differences did not bear any significance, that is, belonging to a high or low income group was not a determining factor in the attitude towards social welfare services or social benefits. According to the research, family and friends still form an informal yet significant support network in people's everyday lives, and its importance has not been diminished by services provided by the welfare state. The Finnish public considers child day care the most reliable form of social welfare services. Indeed, child day care has become the most universal sector of our system of social welfare services. Other services that instil confidence included counselling by social workers and services for people with disabilities. On the other hand, social assistance and home-help services received negative feedback. The negative views were based on a number of arguments. One argument contends that the home-help service system, which was originally intended for universal use, is crumbling. The preventive role of home-help services has been reduced. These results mirror the increasingly popular opinion that social welfare services are not produced for all those who need them, but to an increasing extent for a select few of them. Municipalities are struggling with their finances and this, combined with negative publicity, has damaged the public's trust in some municipal social welfare services. A welfare state never achieves a stable condition, but must develop over time, as the world around it changes. Following the 1990's recession, we are now in a position where we can start to develop a system that responds to the needs of the next generation. Study results indicating new areas of dissatisfaction reflect the need to develop and improve the services provided. It is also increasingly essential that social welfare services pay attention to the opinions of clients and the public. Should the gap between opinions and actual activities increase, the legitimacy of the whole system would be questioned. Currently, the vast majority of Finns consider the system of social welfare services adequate, which provides us with the continuity required to maintain and improve client-oriented and reasonably priced social welfare services. Paying attention to the signals given by clients and the general public, and reacting to them accordingly, will also secure the development and legitimacy of the system in the future.

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The evacuation of Finnish children to Sweden during WW II has often been called a small migration . Historical research on this subject is scarce, considering the great number of children involved. The present research has applied, apart from the traditional archive research, the framework of history-culture developed by Rüsen in order to have an all-inclusive approach to the impact of this historical event. The framework has three dimensions: political, aesthetic and cognitive. The collective memory of war children has also been discussed. The research looks for political factors involved in the evacuations during the Winter War and the Continuation War and the post-war period. The approach is wider than a purely humanitarian one. Political factors have had an impact in both Finland and Sweden, beginning from the decision-making process and ending with the discussion of the unexpected consequences of the evacuations in the Finnish Parliament in 1950. The Winter War (30.11.1939 13.3.1940) witnessed the first child transports. These were also the model for future decision making. The transports were begun on the initiative of Swedes Maja Sandler, the wife of the resigned minister of foreign affairs Rickard Sandler, and Hanna Rydh-Munck af Rosenschöld , but this activity was soon accepted by the Swedish government because the humanitarian help in the form of child transports lightened the political burden of Prime Minister Hansson, who was not willing to help Finland militarily. It was help that Finland never asked for and it was rejected at the beginning. The negative response of Minister Juho Koivisto was not taken very seriously. The political forces in Finland supporting child transports were stronger than those rejecting them. The major politicians in support belonged to Finland´s Swedish minority. In addition, close to 1 000 Finnish children remained in Sweden after the Winter War. No analysis was made of the reasons why these children did not return home. A committee set up to help Finland and Norway was established in Sweden in 1941. Its chairman was Torsten Nothin, an influential Swedish politician. In December 1941 he appealed to the Swedish government to provide help to Finnish children under the authority of The International Red Cross. This plea had no results. The delivery of great amounts of food to Finland, which was now at war with Great Britain, had automatically caused reactions among the allies against the Swedish imports through Gothenburg. This included the import of oil, which was essential for the Swedish navy and air force. Oil was later used successfully to force a reduction in commerce between Sweden and Finland. The contradiction between Sweden´s essential political interests and humanitarian help was solved in a way that did not harm the country´s vital political interests. Instead of delivering help to Finland, Finnish children were transported to Sweden through the organisations that had already been created. At the beginning of the Continuation War (25.6.1941 27.4.1945) negative opinion regarding child transports re-emerged in Finland. Karl-August Fagerholm implemented the transports in September 1941. In 1942, members of the conservative parties in the Finnish Parliament expressed their fear of losing the children to the Swedes. They suggested that Finland should withdraw from the inter-Nordic agreement, according to which the adoptions were approved by the court of the country where the child resided. This initiative failed. Paavo Virkkunen, an influential member of the conservative party Kokoomus in Finland, favoured the so-called good-father system, where help was delivered to Finland in the form of money and goods. Virkkunen was concerned about the consequences of a long stay in a Swedish family. The risk of losing the children was clear. The extreme conservative party (IKL, the Patriotic Movement of the Finnish People) wanted to alienate Finland from Sweden and bring Finland closer to Germany. Von Blücher, the German ambassador to Finland, had in his report to Berlin, mentioned the political consequences of the child transports. Among other things, they would bring Finland and Sweden closer to each other. He had also paid attention to the Nordic political orientation in Finland. He did not question or criticize the child transports. His main interest was to increase German political influence in Finland, and the Nordic political orientation was an obstacle. Fagerholm was politically ill-favoured by the Germans, because he had a strong Nordic political disposition and had criticised Germany´s activities in Norway. The criticism of child transports was at the same time criticism of Fagerholm. The official censorship organ of the Finnish government (VTL) denied the criticism of child transports in January 1942. The reasons were political. Statements made by members of the Finnish Parliament were also censored, because it was thought that they would offend the Swedes. In addition, the censorship organ used child transports as a means of active propaganda aimed at improving the relations between the two countries. The Finnish Parliament was informed in 1948 that about 15 000 Finnish children still remained in Sweden. These children would stay there permanently. In 1950 the members of the Agrarian Party in Finland stated that Finland should actively strive to get the children back. The party on the left (SKDL, the Democratic Movement of Finnish People) also focused on the unexpected consequences of the child transports. The Social Democrats, and largely Fagerholm, had been the main force in Finland behind the child transports. Members of the SKDL, controlled by Finland´s Communist Party, stated that the war time authorities were responsible for this war loss. Many of the Finnish parents could not get their children back despite repeated requests. The discussion of the problem became political, for example von Born, a member of the Swedish minority party RKP, related this problem to foreign policy by stating that the request to repatriate the Finnish children would have negative political consequences for the relations between Finland and Sweden. He emphasized expressing feelings of gratitude to the Swedes. After the war a new foreign policy was established by Prime Minister (1944 1946) and later President (1946 1956) Juho Kusti Paasikivi. The main cornerstone of this policy was to establish good relations with the Soviet Union. The other, often forgotten, cornerstone was to simultaneously establish good relations with other Nordic countries, especially Sweden, as a counterbalance. The unexpected results of the child evacuation, a Swedish initiative, had violated the good relations with Sweden. The motives of the Democratic Movement of Finnish People were much the same as those of the Patriotic Movement of Finnish People. Only the ideology was different. The Nordic political orientation was an obstacle to both parties. The position of the Democratic Movement of Finnish People was much better than that of the Patriotic Movement of Finnish People, because now one could clearly see the unexpected results, which included human tragedy for the many families who could not be re-united with their children despite their repeated requests. The Swedes questioned the figure given to the Finnish Parliament regarding the number of children permanently remaining in Sweden. This research agrees with the Swedes. In a calculation based on Swedish population registers, the number of these children is about 7 100. The reliability of this figure is increased by the fact that the child allowance programme began in Sweden in 1948. The prerequisite to have this allowance was that the child be in the Swedish population register. It was not necessary for the child to have Swedish nationality. The Finnish Parliament had false information about the number of Finnish children who remained in Sweden in 1942 and in 1950. There was no parliamentary control in Finland regarding child transports, because the decision was made by one cabinet member and speeches by MPs in the Finnish Parliament were censored, like all criticism regarding child transports to Sweden. In Great Britain parliamentary control worked better throughout the whole war, because the speeches regarding evacuation were not censored. At the beginning of the war certain members of the British Labour Party and the Welsh Nationalists were particularly outspoken about the scheme. Fagerholm does not discuss to any great extent the child transports in his memoirs. He does not evaluate the process and results as a whole. This research provides some possibilities for an evaluation of this sort. The Swedish medical reports give a clear picture of the physical condition of the Finnish children when arriving in Sweden. The transports actually revealed how bad the situation of the poorest children was. According to Titmuss, similar observations were made in Great Britain during the British evacuations. The child transports saved the lives of approximately 2 900 children. Most of these children were removed to Sweden to receive treatment for illnesses, but many among the healthy children were undernourished and some suffered from the effects of tuberculosis. The medical inspection in Finland was not thorough. If you compare the figure of 2 900 children saved and returned with the figure of about 7 100 children who remained permanently in Sweden, you may draw the conclusion that Finland as a country failed to benefit from the child transports, and that the whole operation was a political mistake with far-reaching consequenses. The basic goal of the operation was to save lives and have all the children return to Finland after the war. The difficulties with the repatriation of the children were mainly psychological. The level of child psychology in Finland at that time was low. One may question the report by Professor Martti Kaila regarding the adaptation of children to their families back in Finland. Anna Freud´s warnings concerning the difficulties that arise when child evacuees return are also valid in Finland. Freud viewed the emotional life of children in a way different from Kaila: the physical survival of a small child forces her to create strong emotional ties to the person who is looking after her. This, a characteristic of all small children, occurred with the Finnish children too, and it was something the political decision makers in Finland could not see during and after the war. It is a characteristic of all little children. Yet, such experiences were already evident during the Winter War. The best possible solution had been to limit the child transports only to children in need of medical treatment. Children from large and poor families had been helped by organising meals and by buying food from Denmark with Swedish money. Assisting Finland by all possible means should have been the basic goal of Fagerholm in September 1941, when the offer of child transports came from Sweden. Fagerholm felt gratitude towards the Swedes. The risks became clear to him only in 1943. The war children are today a rather scattered and diffuse group of people. Emotionally, part of these children remained in Sweden after the war. There is no clear collective memory, only individual memories; the collective memory of the war children has partly been shaped later through the activities of the war child associations. The main difference between the children evacuated in Finland (for example from Karelia to safer areas with their families) and the war children, who were sent abroad, is that the war children lack a shared story and experience with their families. They were outsiders . The whole matter is sensitive to many of such mothers and discussing the subject has often been avoided in families. The war-time censorship has continued in families through silence and avoidance and Finnish politicians and Finnish families had to face each other on this issue after the war. The lack of all-inclusive historical research has also prevented the formation of a collective awareness among war children returned to Finland or those remaining permanently abroad.. Knowledge of historical facts will help war-children by providing an opportunity to create an all-inclusive approach to the past. Personal experiences should be regarded as part of a large historical entity shadowed by war and where many political factors were at work in both Finland and Sweden. This means strengthening of the cognitive dimension discussed in Rüsen´s all-inclusive historical approach.

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Hantaviruses have a tri-segmented negative-stranded RNA genome. The S segment encodes the nucleocapsid protein (N), M segment two glycoproteins, Gn and Gc, and the L segment the RNA polymerase. Gn and Gc are co-translationally cleaved from a precursor and targeted to the cis-Golgi compartment. The Gn glycoprotein consists of an external domain, a transmembrane domain and a C-terminal cytoplasmic domain. In addition, the S segment of some hantaviruses, including Tula and Puumala virus, have an open reading frame (ORF) encoding a nonstructural potein NSs that can function as a weak interferon antagonist. The mechanisms of hantavirus-induced pathogenesis are not fully understood but it is known that both hemorrhagic fever with renal syndrome (HFRS) and hantavirus (cardio) pulmonary syndrome (HCPS) share various features such as increased capillary permeability, thrombocytopenia and upregulation of TNF-. Several hantaviruses have been reported to induce programmed cell death (apoptosis), such as TULV-infected Vero E6 cells which is known to be defective in interferon signaling. Recently reports describing properties of the hantavirus Gn cytoplasmic tail (Gn-CT) have appeared. The Gn-CT of hantaviruses contains animmunoreceptor tyrosine-based activation motif (ITAM) which directs receptor signaling in immune and endothelial cells; and contain highly conserved classical zinc finger domains which may have a role in the interaction with N protein. More functions of Gn protein have been discovered, but much still remains unknown. Our aim was to study the functions of Gn protein from several aspects: synthesis, degradation and interaction with N protein. Gn protein was reported to inhibit interferon induction and amplication. For this reason, we also carried out projects studying the mechanisms of IFN induction and evasion by hantavirus. We first showed degradation and aggresome formation of the Gn-CT of the apathogenic TULV. It was reported earlier that the degradation of Gn-CT is related to the pathogenicity of hantavirus. We found that the Gn-CT of the apathogenic hantaviruses (TULV, Prospect Hill virus) was degraded through the ubiquitin-proteasome pathway, and TULV Gn-CT formed aggresomes upon treatment with proteasomal inhibitor. Thus the results suggest that degradation and aggregation of the Gn-CT may be a general property of most hantaviruses, unrelated to pathogenicity. Second, we investigated the interaction of TULV N protein and the TULV Gn-CT. The Gn protein is located on the Golgi membrane and its interaction with N protein has been thought to determine the cargo of the hantaviral ribonucleoprotein which is an important step in virus assembly, but direct evidence has not been reported. We found that TULV Gn-CT fused with GST tag expressed in bacteria can pull-down the N protein expressed in mammalian cells; a mutagenesis assay was carried out, in which we found that the zinc finger motif in Gn-CT and RNA-binding motif in N protein are indispensable for the interaction. For the study of mechanisms of IFN induction and evasion by Old World hantavirus, we found that Old World hantaviruses do not produce detectable amounts of dsRNA in infected cells and the 5 -termini of their genomic RNAs are monophosphorylated. DsRNA and tri-phosphorylated RNA are considered to be critical activators of innate immnity response by interacting with PRRs (pattern recognition receptors). We examined systematically the 5´-termini of hantavirus genomic RNAs and the dsRNA production by different species of hantaviruses. We found that no detectable dsRNA was produced in cells infected by the two groups of the old world hantaviruses: Seoul, Dobrava, Saaremaa, Puumala and Tula. We also found that the genomic RNAs of these Old World hantaviruses carry 5´-monophosphate and are unable to trigger interferon induction. The antiviral response is mainly mediated by alpha/beta interferon. Recently the glycoproteins of the pathogenic hantaviruses Sin Nombre and New York-1 viruses were reported to regulate cellular interferon. We found that Gn-CT can inhibit the induction of IFN activation through Toll-like receptor (TLR) and retinoic acid-inducible gene I-like RNA helicases (RLH) pathway and that the inhibition target lies at the level of TANK-binding kinase 1 (TBK-1)/ IKK epislon complex and myeloid differentiation primary response gene (88) (MyD88) / interferon regulatory factor 7 (IRF-7) complex.

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The magnetically induced currents in organic monoring and multiring molecules, in Möbius shaped molecules and in inorganic all-metal molecules have been investigated by means of the Gauge-including magnetically induced currents (GIMIC) method. With the GIMIC method, the ring-current strengths and the ring-current density distributions can be calculated. For open-shell molecules, also the spin current can be obtained. The ring-current pathways and ring-current strengths can be used to understand the magnetic resonance properties of the molecules, to indirectly identify the effect of non-bonded interactions on NMR chemical shifts, to design new molecules with tailored properties and to discuss molecular aromaticity. In the thesis, the magnetic criterion for aromaticity has been adopted. According to this, a molecule which has a net diatropic ring current might be aromatic. Similarly, a molecule which has a net paratropic current might be antiaromatic. If the net current is zero, the molecule is nonaromatic. The electronic structure of the investigated molecules has been resolved by quantum chemical methods. The magnetically induced currents have been calculated with the GIMIC method at the density-functional theory (DFT) level, as well as at the self-consistent field Hartree-Fock (SCF-HF), at the Møller-Plesset perturbation theory of the second order (MP2) and at the coupled-cluster singles and doubles (CCSD) levels of theory. For closed-shell molecules, accurate ring-current strengths can be obtained with a reasonable computational cost at the DFT level and with rather small basis sets. For open-shell molecules, it is shown that correlated methods such as MP2 and CCSD might be needed to obtain reliable charge and spin currents. The basis set convergence has to be checked for open-shell molecules by performing calculations with large enough basis sets. The results discussed in the thesis have been published in eight papers. In addition, some previously unpublished results on the ring currents in the endohedral fullerene Sc3C2@C80 and in coronene are presented. It is shown that dynamical effects should be taken into account when modelling magnetic resonance parameters of endohedral metallofullerenes such as Sc3C2@C80. The ring-current strengths in a series of nano-sized hydrocarbon rings are related to static polarizabilities and to H-1 nuclear magnetic resonance (NMR) shieldings. In a case study on the possible aromaticity of a Möbius-shaped [16]annulene we found that, according to the magnetic criterion, the molecule is nonaromatic. The applicability of the GIMIC method to assign the aromatic character of molecules was confirmed in a study on the ring currents in simple monocylic aromatic, homoaromatic, antiaromatic, and nonaromatic hydrocarbons. Case studies on nanorings, hexaphyrins and [n]cycloparaphenylenes show that explicit calculations are needed to unravel the ring-current delocalization pathways in complex multiring molecules. The open-shell implementation of GIMIC was applied in studies on the charge currents and the spin currents in single-ring and bi-ring molecules with open shells. The aromaticity predictions that are made based on the GIMIC results are compared to other aromaticity criteria such as H-1 NMR shieldings and shifts, electric polarizabilities, bond-length alternation, as well as to predictions provided by the traditional Hückel (4n+2) rule and its more recent extensions that account for Möbius twisted molecules and for molecules with open shells.

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Changes in the structure of plant communities may have much more impact on ecosystem carbon (C) cycling than any phenotypic responses to environmental changes. We studied these impacts via the response of plant litter quality, at the level of species and community, to persistent water-level (WL) drawdown in peatlands. We studied three sites with different nutrient regimes, and water-level manipulations at two time scales. The parameters used to characterize litter quality included extractable substances, cellulose, holocellulose, composition of hemicellulose (neutral sugars, uronic acids), Klason lignin, CuO oxidation phenolic products, and concentrations of C and several nutrients. The litters formed four chemically distinct groups: non-graminoid foliar litters, graminoids, mosses and woody litters. Direct effects of WL drawdown on litter quality at the species level were overruled by indirect effects via changes in litter type composition. The pristine conditions were characterized by Sphagnum moss and graminoid litters. Short-term (years) responses of the litter inputs to WL drawdown were small. In longterm (decades), total litter inputs increased, due to increased tree litter inputs. Simultaneously, the litter type composition and its chemical quality at the community level greatly changed. The changes that we documented will strongly affect soil properties and C cycle of peatlands.

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"We used PCR-DGGE fingerprinting and direct sequencing to analyse the response of fungal and actinobacterial communities to changing hydrological conditions at 3 different sites in a boreal peatland complex in Finland. The experimental design involved a short-term (3 years; STD) and a long-term (43 years; LTD) water-level drawdown. Correspondence analyses of DGGE bands revealed differences in the communities between natural sites representing the nutrient-rich mesotrophic fen, the nutrient-poorer oligotrophic fen, and the nutrient-poor ombrotrophic bog. Still, most fungi and actinobacteria found in the pristine peatland seemed robust to the environmental variables. Both fungal and actinobacterial diversity was higher in the fens than in the bog. Fungal diversity increased significantly after STD whereas actinobacterial diversity did not respond to hydrology. Both fungal and actinobacterial communities became more similar between peatland types after LTD, which was not apparent after STD. Most sequences clustered equally between the two main fungal phyla Ascomycota and Basidiomycota. Sequencing revealed that basidiomycetes may respond more (either positively or negatively) to hydrological changes than ascomycetes. Overall, our results suggest that fungal responses to water-level drawdown depend on peatland type. Actinobacteria seem to be less sensitive to hydrological changes, although the response of some may similarly depend on peatland type. (C) 2009 Elsevier Ltd. All rights reserved."

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Hypertension is one of the major risk factors for cardiovascular morbidity. The advantages of antihypertensive therapy have been clearly demonstrated, but only about 30% of hypertensive patients have their blood pressure (BP) controlled by such treatment. One of the reasons for this poor BP control may lie in the difficulty in predicting BP response to antihypertensive treatment. The average BP reduction achieved is similar for each drug in the main classes of antihypertensive agents, but there is a marked individual variation in BP responses to any given drug. The purpose of the present study was to examine BP response to four different antihypertensive monotherapies with regard to demographic characteristics, laboratory test results and common genetic polymorphisms. The subjects of the present study are participants in the pharmacogenetic GENRES Study. A total of 208 subjects completed the whole study protocol including four drug treatment periods of four weeks, separated by four-week placebo periods. The study drugs were amlodipine, bisoprolol, hydrochlorothiazide and losartan. Both office (OBP) and 24-hour ambulatory blood pressure (ABP) measurements were carried out. BP response to study drugs were related to basic clinical characteristics, pretreatment laboratory test results and common polymorphisms in genes coding for components of the renin-angiotensin system, alpha-adducin (ADD1), beta1-adrenergic receptor (ADRB1) and beta2-adrenergic receptor (ADRB2). Age was positively correlated with BP responses to amlodipine and with OBP and systolic ABP responses to hydrochlorothiazide, while body mass index was negatively correlated with ABP responses to amlodipine. Of the laboratory test results, plasma renin activity (PRA) correlated positively with BP responses to losartan, with ABP responses to bisoprolol, and negatively with ABP responses to hydrochlorothiazide. Uniquely to this study, it was found that serum total calcium level was negatively correlated with BP responses to amlodipine, whilst serum total cholesterol level was negatively correlated with ABP responses to amlodipine. There were no significant associations of angiotensin II type I receptor 1166A/C, angiotensin converting enzyme I/D, angiotensinogen Met235Thr, ADD1 Gly460Trp, ADRB1 Ser49Gly and Gly389Arg and ADRB2 Arg16Gly and Gln27Glu polymorphisms with BP responses to the study drugs. In conclusion, this study confirmed the relationship between pretreatment PRA levels and response to three classes of antihypertensive drugs. This study is the first to note a significant inverse relation between serum calcium level and responsiveness to a calcium channel blocker. However, this study could not replicate the observations that common polymorphisms in angiotensin II type I receptor, angiotensin converting enzyme, angiotensinogen, ADD1, ADRB1, or ADRB2 genes can predict BP response to antihypertensive drugs.