983 resultados para Ledeboer, Lambertus Vincentius, 1795-1891


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There is a relative absence of sociological and cultural research on how people deal with the death of a family member in the contemporary western societies. Research on this topic has been dominated by the experts of psychology, psychiatry and therapy, who mention the social context only in passing, if at all. This gives an impression that the white westerners bereavement experience is a purely psychological phenomenon, an inner journey, which follows a natural, universal path. Yet, as Tony Walter (1999) states, ignoring the influence of culture not only impoverishes the understanding of those work with bereaved people, but it also impoverishes sociology and cultural studies by excluding from their domain a key social phenomenon. This study explores the cultural dimension of grief through narratives told by fifteen of recently bereaved Finnish women. Focussing on one sex only, the study rests on the assumption of the gendered nature of bereavement experience. However, the aim of the study is not to pinpoint the gender differences in grief and mourning, but to shed light on women s ways of dealing with the loss of a loved one in a social context. Furthermore, the study focuses on a certain kind of loss: the death of an elderly parent. Due to the growth in the life expectancy rate, this has presumably become the most typical type of bereavement in contemporary, ageing societies. Most of population will face the death of a parent as they reach the middle years of the life course. The data of this study is gathered with interviews, in which the interviewees were invited to tell a narrative of their bereavement. Narrative constitutes a central concept in this study. It refers to a particular form of talk, which is organised around consequential events. But there are also other, deeper layers that have been added to this concept. Several scholars see narratives as the most important way in which we make sense of experience. Personal narratives provide rich material for mapping the interconnections between individual and culture. As a form of thought, narrative marries singular circumstances with shared expectations and understandings that are learned through participation in a specific culture (Garro & Mattingly 2000). This study attempts to capture the cultural dimension of narrative with the concept of script , which originates in cognitive science (Schank & Abelson 1977) and has recently been adopted to narratology (Herman 2002). Script refers to a data structure that informs how events usually unfold in certain situations. Scripts are used in interpreting events and representing them verbally to others. They are based on dominant forms of knowledge that vary according to time and place. The questions that were posed in this study are the following. What kind of experiences bereaved daughters narrate? What kind of cultural scripts they employ as they attempt to make sense of these experiences? How these scripts are used in their narratives? It became apparent that for the most of the daughters interviewed in this study the single most important part of the bereavement narrative was to form an account of how and why the parent died. They produced lengthy and detailed descriptions of the last stage of a parent s life in contrast with the rest of the interview. These stories took their start from a turn in the parent s physical condition, from which the dying process could in retrospect be seen to have started, and which often took place several years before the death. In addition, daughters also talked about their grief reactions and how they have adjusted to a life without the deceased parent. The ways in which the last stage of life was told reflect not only the characteristic features of late modernity but also processes of marginalisation and exclusion. Revivalist script and medical script, identified by Clive Seale as the dominant, competing models for dying well in the late modern societies, were not widely utilised in the narratives. They could only be applied in situations in which the parent had died from cancer and at somewhat younger age than the average. Death that took place in deep old age was told in a different way. The lack of positive models for narrating this kind of death was acknowledged in the study. This can be seen as a symptom of the societal devaluing of the deaths of older people and it affects also daughters accounts of their grief. Several daughters told about situations in which their loss, although subjectively experienced, was nonetheless denied by other people.

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On a journey from marginal to mainstream? The lifestyle and recovery of former drug users This thesis studies the lifestyle and recovery of former users of illicit drugs through their experiences. The study describes the life of people with drug problems both during the time they used drugs regularly and after they stopped the use entirely. The focus is on the development of the lifestyle of 32 persons who no longer use drugs. They may have stopped using drugs independently or with the help of a treatment. In this study, persons who have given up drug use with the help of a psychosocially oriented treatment are called non-medicinally treated former users (n=19) whereas opioid addicts who have stopped using drugs through substitution treatment are referred to as substitution treatment patients (n=13). The research material was gathered from theme interviews. The criteria for the focus group of the study included the following: a) the interviewees had had a serious drug problem in their past; b) they had not used drugs for at least one year prior to the interview; c) they were not in an institutional care at the time of the study. This thesis is basically a lifestyle study in which the aspects of lifestyle are used to describe the everyday life of former drug users. The study reviews the whole spectrum of everyday routines, especially the social interaction and subjective experiences of people. The second concept used in this study is recovery, which is described as a process that starts from the abstinence from substances and adoption of the recovery culture and continues as a comprehensive change of the lifestyle, identity and values of an individual. Disengaging from a drug-oriented lifestyle and connected social network as well as finding an individual frame of reference is a demanding process. Years of drug use have often caused complex health and social disadvantages as well as problems with work, education, livelihood, accommodation and human relationships. The effect of the past on the present arises at all levels. The interviews revealed a recovery culture maintaining the lifestyle as well as an adaptive and optimistic approach to the future among those participating in the study. The study shows that an adequate distance from acute substance use is a precondition for the beginning of the recovery process, yet abstinence in itself tells nothing about the actual recovery. The study describes how some recovering users find a meaning in life easily whereas others have to work actively for their recovery. Detaching oneself from the feeling of adopted abnormality connected with substance addiction forms an important basis for satisfying abstinence. Peer groups support the development of counter-cultures and abstinence or the support is received from the community formed in the substitution treatment clinic.

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Microorganisms exist predominantly as sessile multispecies communities in natural habitats. Most bacterial species can form these matrix-enclosed microbial communities called biofilms. Biofilms occur in a wide range of environments, on every surface with sufficient moisture and nutrients, also on surfaces in industrial settings and engineered water systems. This unwanted biofilm formation on equipment surfaces is called biofouling. Biofouling can significantly decrease equipment performance and lifetime and cause contamination and impaired quality of the industrial product. In this thesis we studied bacterial adherence to abiotic surfaces by using coupons of stainless steel coated or not coated with fluoropolymer or diamond like carbon (DLC). As model organisms we used bacterial isolates from paper machines (Meiothermus silvanus, Pseudoxanthomonas taiwanensis and Deinococcus geothermalis) and also well characterised species isolated from medical implants (Staphylococcus epidermidis). We found that coating of steel surface with these materials reduced its tendency towards biofouling: Fluoropolymer and DLC coatings repelled all four biofilm formers on steel. We found great differences between bacterial species in their preference of surfaces to adhere as well as their ultrastructural details, like number and thickness of adhesion organelles they expressed. These details responded differently towards the different surfaces they adhered to. We further found that biofilms of D. geothermalis formed on titanium dioxide coated coupons of glass, steel and titanium, were effectively removed by photocatalytic action in response to irradiation at 360 nm. However, on non-coated glass or steel surfaces irradiation had no detectable effect on the amount of bacterial biomass. We showed that the adhesion organelles of bacteria on illuminated TiO2 coated coupons were complety destroyed whereas on non-coated coupons they looked intact when observed by microscope. Stainless steel is the most widely used material for industrial process equipments and surfaces. The results in this thesis showed that stainless steel is prone to biofouling by phylogenetically distant bacterial species and that coating of the steel may offer a tool for reduced biofouling of industrial equipment. Photocatalysis, on the other hand, is a potential technique for biofilm removal from surfaces in locations where high level of hygiene is required. Our study of natural biofilms on barley kernel surfaces showed that also there the microbes possessed adhesion organelles visible with electronmicroscope both before and after steeping. The microbial community of dry barley kernels turned into a dense biofilm covered with slimy extracellular polymeric substance (EPS) in the kernels after steeping in water. Steeping is the first step in malting. We also presented evidence showing that certain strains of Lactobacillus plantarum and Wickerhamomyces anomalus, when used as starter cultures in the steeping water, could enter the barley kernel and colonise the tissues of the barley kernel. By use of a starter culture it was possible to reduce the extensive production of EPS, which resulted in a faster filtration of the mash.

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Pristine peatlands are carbon (C) accumulating wetland ecosystems sustained by a high water level (WL) and consequent anoxia that slows down decomposition. Persistent WL drawdown as a response to climate and/or land-use change directly affects decomposition: increased oxygenation stimulates decomposition of the old C (peat) sequestered under prior anoxic conditions. Responses of the new C (plant litter) in terms of quality, production and decomposability, and the consequences for the whole C cycle of peatlands are not fully understood. WL drawdown induces changes in plant community resulting in shift in dominance from Sphagnum and graminoids to shrubs and trees. There is increasing evidence that the indirect effects of WL drawdown via the changes in plant communities will have more impact on the ecosystem C cycling than any direct effects. The aim of this study is to disentangle the direct and indirect effects of WL drawdown on the new C by measuring the relative importance of 1) environmental parameters (WL depth, temperature, soil chemistry) and 2) plant community composition on litter production, microbial activity, litter decomposition rates and, consequently, on the C accumulation. This information is crucial for modelling C cycle under changing climate and/or land-use. The effects of WL drawdown were tested in a large-scale experiment with manipulated WL at two time scales and three nutrient regimes. Furthermore, the effect of climate on litter decomposability was tested along a north-south gradient. Additionally, a novel method for estimating litter chemical quality and decomposability was explored by combining Near infrared spectroscopy with multivariate modelling. WL drawdown had direct effects on litter quality, microbial community composition and activity and litter decomposition rates. However, the direct effects of WL drawdown were overruled by the indirect effects via changes in litter type composition and production. Short-term (years) responses to WL drawdown were small. In long-term (decades), dramatically increased litter inputs resulted in large accumulation of organic matter in spite of increased decomposition rates. Further, the quality of the accumulated matter greatly changed from that accumulated in pristine conditions. The response of a peatland ecosystem to persistent WL drawdown was more pronounced at sites with more nutrients. The study demonstrates that the shift in vegetation composition as a response to climate and/or land-use change is the main factor affecting peatland ecosystem C cycle and thus dynamic vegetation is a necessity in any models applied for estimating responses of C fluxes to changes in the environment. The time scale for vegetation changes caused by hydrological changes needs to extend to decades. This study provides grouping of litter types (plant species and part) into functional types based on their chemical quality and/or decomposability that the models could utilize. Further, the results clearly show a drop in soil temperature as a response to WL drawdown when an initially open peatland converts into a forest ecosystem, which has not yet been considered in the existing models.

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Parkinson s disease (PD) is a neurodegenerative disorder associated with a progressive loss of dopaminergic neurons of the substantia nigra (SN). Current therapies of PD do not stop the progression of the disease and the efficacy of these treatments wanes over time. Neurotrophic factors are naturally occurring proteins promoting the survival and differentiation of neurons and the maintenance of neuronal contacts. Neurotrophic factors are attractive candidates for neuroprotective or even neurorestorative treatment of PD. Thus, searching for and characterizing trophic factors are highly important approaches to degenerative diseases. CDNF (cerebral dopamine neurotrophic factor) and MANF (mesencephalic astrocyte-derived neurotrophic factor) are secreted proteins that constitute a novel, evolutionarily conserved neurotrophic factor family expressed in vertebrates and invertebrates. The present study investigated the neuroprotective and restorative effects of human CDNF and MANF in rats with unilateral partial lesion of dopamine neurons by 6-hydroxydopamine (6-OHDA) using both behavioral (amphetamine-induced rotation) and immunohistochemical analyses. We also investigated the distribution and transportation profiles of intrastriatally injected CDNF and MANF in rats. Intrastriatal CDNF and MANF protected nigrostriatal dopaminergic neurons when administered six hours before or four weeks after the neurotoxin 6-OHDA. More importantly, the function of the lesioned nigrostriatal dopaminergic system was partially restored even when the neurotrophic factors were administered four weeks after 6-OHDA. A 14-day continuous infusion of CDNF but not of MANF restored the function of the midbrain neural circuits controlling movement when initiated two weeks after unilateral injection of 6-OHDA. Continuous infusion of CDNF also protected dopaminergic TH-positive cell bodies from toxin-induced degeneration in the substantia nigra pars compacta (SNpc) and fibers in the striatum. When injected into the striatum, CDNF and GDNF had similar transportation profiles from the striatum to the SNpc; thus CDNF may act via the same nerve tracts as GDNF. Intrastriatal MANF was transported to cortical areas which may reflect a mechanism of neurorestorative action that is different from that of CDNF and GDNF. CDNF and MANF were also shown to distribute more readily than GDNF. In conclusion, CDNF and MANF are potential therapeutic proteins for the treatment of PD.

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Wood-degrading fungi are able to degrade a large range of recalcitrant pollutants which resemble the lignin biopolymer. This ability is attributed to the production of lignin-modifying enzymes, which are extracellular and non-specific. Despite the potential of fungi in bioremediation, there is still an understanding gap in terms of the technology. In this thesis, the feasibility of two ex situ fungal bioremediation methods to treat contaminated soil was evaluated. Treatment of polycyclic aromatic hydrocarbons (PAHs)-contaminated marsh soil was studied in a stirred slurry-phase reactor. Due to the salt content in marsh soil, fungi were screened for their halotolerance, and the white-rot fungi Lentinus tigrinus, Irpex lacteus and Bjerkandera adusta were selected for further studies. These fungi degraded 40 - 60% of a PAH mixture (phenanthrene, fluoranthene, pyrene and chrysene) in a slurry-phase reactor (100 ml) during 30 days of incubation. Thereafter, B. adusta was selected to scale-up and optimize the process in a 5 L reactor. Maximum degradation of dibenzothiophene (93%), fluoranthene (82%), pyrene (81%) and chrysene (83%) was achieved with the free mycelium inoculum of the highest initial biomass (2.2 g/l). In autoclaved soil, MnP was the most important enzyme involved in PAH degradation. In non-sterile soil, endogenous soil microbes together with B. adusta also degraded the PAHs extensively, suggesting a synergic action between soil microbes and the fungus. A fungal solid-phase cultivation method to pretreat contaminated sawmill soil with high organic matter content was developed to enhance the effectiveness of the subsequent soil combustion. In a preliminary screening of 146 fungal strains, 28 out of 52 fungi, which extensively colonized non-sterile contaminated soil, were litter-decomposing fungi. The 18 strains further selected were characterized by their production of lignin-modifying and hydrolytic enzymes, of which MnP and endo-1,4-β-glucanase were the main enzymes during cultivation on Scots pine (Pinus sylvestris) bark. Of the six fungi selected for further tests, Gymnopilus luteofolius, Phanerochaete velutina, and Stropharia rugosoannulata were the most active soil organic matter degraders. The results showed that a six-month pretreatment of sawmill soil would result in a 3.5 - 9.5% loss of organic matter, depending on the fungus applied. The pretreatment process was scaled-up for a 0.56 m3 reactor, in which perforated plastic tubes filled with S. rugosoannulata growing on pine bark were introduced into the soil. The fungal pretreatment resulted in a soil mass loss of 30.5 kg, which represents 10% of the original soil mass (308 kg). Despite the fact that Scots pine bark contains several antimicrobial compounds, it was a suitable substrate for fungal growth and promoter of the production of oxidative enzymes, as well as an excellent and cheap natural carrier of fungal mycelium. This thesis successfully developed two novel fungal ex situ bioremediation technologies and introduce new insights for their further full-scale application. Ex situ slurry-phase fungal reactors might be applied in cases when the soil has a high water content or when the contaminant bioavailability is low; for example, in wastewater treatment plants to remove pharmaceutical residues. Fungal solid-phase bioremediation is a promising remediation technology to ex situ or in situ treat contaminated soil.