13 resultados para 630107 Minor livestock (e.g. horses, goats, deer)

em Helda - Digital Repository of University of Helsinki


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Increasing antimicrobial resistance in bacteria has led to the need for better understanding of antimicrobial usage patterns. In 1999, the World Organisation for Animal Health (OIE) recommended that an international ad hoc group should be established to address human and animal health risks related to antimicrobial resistance and the contribution of antimicrobial usage in veterinary medicine. In European countries the need for continuous recording of the usage of veterinary antimicrobials as well as for animal species-specific and indication-based data on usage has been acknowledged. Finland has been among the first countries to develop prudent use guidelines in veterinary medicine, as the Ministry of Agriculture and Forestry issued the first animal species-specific indication-based recommendations for antimicrobial use in animals in 1996. These guidelines have been revised in 2003 and 2009. However, surveillance on the species-specific use of antimicrobials in animals has not been performed in Finland. This thesis provides animal species-specific information on indication-based antimicrobial usage. Different methods for data collection have been utilized. Information on antimicrobial usage in animals has been gathered in four studies (studies A-D). Material from studies A, B and C have been used in an overlapping manner in the original publications I-IV. Study A (original publications I & IV) presents a retrospective cross-sectional survey on prescriptions for small animals at the Veterinary Teaching Hospital of the University of Helsinki. Prescriptions for antimicrobial agents (n = 2281) were collected and usage patterns, such as the indication and length of treatment, were reviewed. Most of the prescriptions were for dogs (78%), and primarily for the treatment of skin and ear infections most of which were treated with cephalexin for a median period of 14 days. Prescriptions for cats (18%) were most often for the treatment of urinary tract infections with amoxicillin for a median length of 10 days. Study B (original publication II) was a retrospective cross-sectional survey where prescriptions for animals were collected from 17 University Pharmacies nationwide. Antimicrobial prescriptions (n = 1038) for mainly dogs (65%) and cats (19%) were investigated. In this study, cephalexin and amoxicillin were also the most frequently used drugs for dogs and cats, respectively. In study C (original publications III & IV), the indication-based usage of antimicrobials of practicing veterinarians was analyzed by using a prospective questionnaire. Randomly selected practicing veterinarians in Finland (n = 262) recorded all their antimicrobial usage during a 7-day study period. Cattle (46%) with mastitis were the most common patients receiving antimicrobial treatment, generally intramuscular penicillin G or intramammary treatment with ampicillin and cloxacillin. The median length of treatment was four days, regardless of the route of administration. Antimicrobial use in horses was evaluated in study D, the results of which are previously unpublished. Firstly, data collected with the prospective questionnaire from the practicing veterinarians showed that horses (n = 89) were frequently treated for skin or wound infections by using penicillin G or trimethoprim-sulfadiazine. The mean duration of treatment was five to seven days. Secondly, according to retrospective data collected from patient records, horses (n = 74) that underwent colic surgery at the Veterinary Teaching Hospital of the University of Helsinki were generally treated according to national and hospital recommendations; penicillin G and gentamicin was administered preoperatively and treatment was continued for a median of three days postoperatively. In conclusion, Finnish veterinarians followed well the national prudent use guidelines. Narrow-spectrum antimicrobials were preferred and, for instance, fluoroquinolones were used sparingly. Prescription studies seemed to give good information on antimicrobials usage, especially when combined with complementary information from patient records. A prospective questionnaire study provided a fair amount of valuable data on several animal species. Electronic surveys are worthwhile exploiting in the future.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

What are the musical features that turn a song into a hit? The aim of this research is to explore the musical features of hit tunes by studying the 224 most popular Finnish evergreens from the 1930s to the 1990s. It is remarkable, that 80-90% of Finnish oldies are in a minor key, though parallel major keys have also been widely employed within single pieces through, for example, modulations. Furthermore, melodies are usually diatonic, staying mostly in the same key. Consequently, chromatically altered tones in the melody and short modulations in the bridge sections become more prominent. I have concentrated in particular on the melodic lines in order to find the most typical melodic formulas from the data. These analyzed melodic formulas play an important role, because they serve as leading phrases and punchlines in songs. Analysis has revealed three major melodic formulas, which most often appear in the melodic lines of hit tunes. All of these formulas share common thematic ground, because they originate from the triadic tonic chord. Because the tonic chord is the most conventional opening chord in the verse parts, it is logical that these formulas occur most often in verses. The strong dominance of these formulas is very much a result of the rhythmic flexibility they possess; for instance, they can be found in every musical style from waltz to foxtrot. Alongside the major formulas lies a miscellaneous group of other tonic-related melodic formulas. One group of melodic formulas consists of melodic quotations. These quotations appear in a different musical context, for instance in a harmonically altered form, and are therefore often difficult to recognize as such. Yet despite the contextual manipulation, the distinctive character of the cited melody usually remains the same. Composers have also made use of certain popular chord-progressions in order to create new but familiar-sounding melodies. The most important individual progression in this case is what is known as a "circle of fifths" and its shortened, prolonged and altered versions. Because that progression is harmonically strong, it is also a contrastive tool used especially in chorus parts and middle sections (AABA). I have also paid attention to ragtime and jazz influences, which can be found in harmony parts and certain melody notes, which extend, suspend or alter the accompaning chords. Other influences from jazz and ragtime in the Finnish evergreen are evident in the use of typical Tin Pan Alley popular song forms. The most important is the AABA form, which dominates over the data along with the verse/chorus-type popular song form. To briefly illustrate the main results, the basic concept of the hit tune can be traced back to Tin Pan Alley songs, whereas the major stylistic aspects, such as minor keys and musical styles, bear influences from Russian, Western European, and Finnish traditions.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The prominent roles of birds, often mentioned in historical sources, are not well reflected in archaeological research. Absence or scarcity of bird bones in archaeological assemblages has been often seen as indication of a minor role of birds in the prehistoric economy or ideology, or explained by taphonomic loss. Few studies exist where birds form the basis for extensive archaeological interpretation. In this doctoral dissertation bird bone material from various Stone Age sites in the Baltic Sea region is investigated. The study period is approximately 7000-3400 BP, comprising mainly Neolithic cultures. The settlement material comes from Finland, Åland, Gotland, Saaremaa and Hiiumaa. Osteological materials are used for studying the economic and cultural importance of birds, fowling methods and principal fowling seasons. The bones were identified and earlier identifications partially checked with help of a reference material of modern skeletons. Fracture analysis was used in order to study the deposition history of bones at Ajvide settlement site. Birds in burials at two large cemeteries, Ajvide on Gotland and Zvejnieki in northern Latvia were investigated in order to study the roles of birds in burial practices. My study reveals that the economic importance of birds is at least seasonally often more prominent than usually thought, and varies greatly in different areas. Fowling has been most important in coastal areas, and especially during the breeding season. Waterbirds and grouse species were generally the most important groups in Finnish Stone Age economy. The identified species composition shows much resemblance to contemporary hunting with species such as the mallard and capercaillie commonly found. Burial materials and additional archaeological evidence from Gotland, Latvia and some other parts of northern Europe indicate that birds –e.g., jay, whooper swan, ducks – have been socially and ideologically important for the studied groups (indicating a place in the belief system, e.g. clan totemism). The burial finds indicate that some common ideas about waterbirds (perhaps as messengers or spirit helpers) might have existed in the northern European Stone Age.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In her thesis, Kaisa Kaakinen analyzes how the German emigrant author W. G. Sebald (1944-2001) uses architecture and photography in his last novel "Austerlitz" to represent time, history and remembering. Sebald describes time in spatial terms: it is like a building, the rooms and chambers of which are connected to each other. The poetics of spatial time manifests itself on multiple levels of the text. Kaakinen traces it in architectural representations, photographic images, intertextuality, as well as in the form of the text, using the concept of spatial form by Joseph Frank. Architectural and photographic representations serve as meeting points for different aspects and angles of the novel and illustrate the idea of a layered present that has multiple connections to the past. The novel tells a story of Jacques Austerlitz, who as a small child was sent from Prague to Britain in one of the so-called Kindertransports that saved children from Central Europe occupied by the National Socialists. Only gradually he remembers his Jewish parents, who have most likely perished in Nazi concentration camps. The novel brings the problematic of writing about another person's past to the fore by the fact that Austerlitz's story is told by an anonymous narrator, Austerlitz's interlocutor, who listens to and writes down Austerlitz's story. Kaakinen devotes the final part of her thesis to study the demands of representing a historical trauma, drawing on authors such as Dominick LaCapra and Michael Rothberg. Through the analysis of architectural and photographic representations in the novel, she demonstrates how Austerlitz highlights the sense of singularity and inaccessibility of memories of an individual, while also stressing the necessity - and therefore a certain kind of possibility - of passing these memories to another person. The coexistence of traumatic narrowness and of the infinity of history is reflected in ambivalent buildings. Some buildings in the novel resemble reversible figures: they can be perceived simultaneously as ruins and as construction sites. Buildings are also shown to be able to both cover and preserve memories - an idea that also is repeated in the use of photography, which tends to both replace memories and cause an experience of the presence of an absent thing. Commenting and critisizing some recent studies on Sebald, the author develops a reading which stresses the ambivalence inherent in Sebald's view on history and historiography. Austerlitz shows the need to recognize the inevitable absence of the past as well as the distance from the experiences of others. Equally important, however, is the refusal to give up narrating the past: Sebald's novel stresses the necessity to preserve the sites of the past, which carry silent traces of vanished life. The poetics of Austerlitz reflects the paradox of the simultaneous impossibility and indispensability of writing history.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This research deals with direct speech quotations in magazine articles through two questions: As my major research question, I study the functions of speech quotations based on a data consisting of six literary-journalistic magazine articles. My minor research question builds on the fact that there is no absolute relation between the sound waves of the spoken language and the graphemes of the written one. Hence, I study the general thoughts on how utterances should be arranged in the written form based on a large review of literature and textbooks on journalistic writing as well as interviews I have made with magazine writers and editors, and the Council of Mass Media in Finland. To support my main research questions, I also examine the reference system of the Finnish language, define the aspects of the literary-journalistic article and study vernacular cues in written speech quotations. FUNCTIONS OF QUOTATIONS. I demonstrate the results of my analysis with a six-pointed apparatus. It is a continuum which extends from the structural level of text, all the way through the explicit functions, to the implicit functions of the quotation. The explicit functions deal with the question of what is the content, whereas the implicit ones base mainly on the question how the content is presented. 1. The speech quotation is an distinctive element in the structure of the magazine article. Thereby it creates a rhythm for the text, such as episodes, paragraphs and clauses. 2. All stories are told through a plot, and in magazine articles, the speech quotations are one of the narrative elements that propel the plot forward. 3. The speech quotations create and intensify the location written in the story. This location can be a physical one but also a social one, in which case it describes the atmosphere and mood in the physical environment and of the story characters. 4. The quotations enhance the plausibility of the facts and assumptions presented in the article, and moreover, when a text is placed between quotation marks, the reader can be assured that the text has been reproduced in the authentic verbatim way. 5. Speech quotations tell about the speaker's unique way of using language and the first-hand experiences of the person quoted. 6. The sixth function of speech quotations is probably the most essential one: the quotations characterize the quoted speaker. In other words, in addition to the propositional content of the utterance, the way in which it has been said transmits a lot of the speaker's character (e.g. nature, generation, behaviour, education, attitudes etc.). It is important to notice, that these six functions of my speech quotation apparatus do not exlude one another. It means that every speech quotation basically includes all of the functions discussed above. However, in practice one or more of them have a principal role, while the others play a subsidiary role. HOW TO MAKE QUOTATIONS? It is not suprising that the field of journalism (textbooks, literature and interviews) holds heterogeneous and unestablished thoughts on how the spoken language should be arranged in written quotations, which is my minor research question. However, the most frequent and distinctive aspects can be depicted in a couple of words: serve the reader and respect the target person. Very common advice on how to arrange the quotations is − firstly, to delete such vernacular cues (e.g. repetitions and ”expletives”) that are common in spoken communication, but purposeless in the written language. − secondly, to complete the phonetic word forms of the spoken language into a more reader-friendly form (esim. punanen → punainen, 'red'), and − thirdly, to enhance the independence of clauses from the (authentic) context and to toughen reciprocal links between them. According to the knowledge of the journalistic field, utterances recorded in different points in time of an interview or a data-collecting session can be transferred as consecutive quotations or even merged together. However, if there is any temporal-spatial location written in the story, the dialogue of the story characters should also be situated in an authentic context – chronologically in the right place in the continuum of the events. To summarize, the way in which the utterances should be arranged into written speech quotations is always situationally-specific − and it is strongly based on the author's discretion.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Adverse health behaviors as well as obesity are key risk factors for chronic diseases. Working conditions also contribute to health outcomes. It is possible that the effects of psychosocially strenuous working conditions and other work-related factors on health are, to some extent, explained by adverse behaviors. Previous studies about the associations between several working conditions and behavioral outcomes are, however, inconclusive. Moreover, the results are derived mostly from male populations, one national setting only, and with limited information about working conditions and behavioral risk factors. Thus, with an interest in employee health, this study was set to focus on behavioral risk factors among middle-aged employees. More specifically, the main aim was to shed light on the associations of various working conditions with health behaviors, weight gain, obesity, and symptoms of angina pectoris. In addition to national focus, international comparisons were included to test the associations across countries thereby aiming to produce a more comprehensive picture. Furthermore, a special emphasis was on gaining new evidence in these areas among women. The data derived from the Helsinki Health Study, and from collaborative partners at the Whitehall II Study, University College London, UK, and the Toyama University, Japan. In Helsinki, the postal questionnaires were mailed in 2000-2002 to employees of the City of Helsinki, aged 40 60 years (n=8960). The questionnaire data covered e.g., socio-economic indicators and working conditions such as Karasek s job demands and job control, work fatigue, working overtime, work-home interface, and social support. The outcome measures consisted of smoking, drinking, physical activity, food habits, weight gain, obesity, and symptoms of angina pectoris. The international cohorts included comparable data. Logistic regression analysis was used. The models were adjusted for potential confounders such as age, education, occupational class, and marital status subject to specific aims. The results showed that working conditions were mostly unassociated with health behaviors, albeit some associations were found. Low job strain was associated with healthy food habits and non-smoking among women in Helsinki. Work fatigue, in turn, was related to drinking among men and physical inactivity among women. Work fatigue and working overtime were associated with weight gain in Helsinki among both women and men. Finally, work fatigue, low job control, working overtime, and physically strenuous work were associated with symptoms of angina pectoris among women in Helsinki. Cross-country comparisons confirmed mostly non-existent associations. High job strain was associated with physical inactivity and smoking, and passive work with physical inactivity and less drinking. Working overtime, in turn, related to non-smoking and obesity. All these associations were, however, inconsistent between cohorts and genders. In conclusion, the associations of the studied working conditions with the behavioral risk factors lacked general patters, and were, overall, weak considering the prevalence of psychosocially strenuous work and overtime hours. Thus, based on this study, the health effects of working conditions are likely to be mediated by adverse behaviors only to a minor extent. The associations of work fatigue and working overtime with weight gain and symptoms of angina pectoris are, however, of potential importance to the subsequent health and work ability of employees.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is a recently characterized cancer syndrome which predisposes to cutaneous and uterine leiomyomas as well as renal cell carcinoma (RCC). Uterine leiomyosarcoma (ULMS) has also been observed in certain Finnish HLRCC families. The predisposing gene for this syndrome, fumarate hydratase (FH), was identified in 2002. The well-known function of FH is in the tricarboxylic acid cycle (TCAC) in the energy metabolism of cells. As FH is a novel cancer gene, the role of FH mutations in tumours is in general unknown. Similarly, the mechanisms through which defective FH is associated with tumourigenesis are unclear. The loss of a wild type allele has been observed in virtually all HLRCC patients tumours and the FH enzyme activities are either totally lost or remarkably reduced in the tissues of mutation carrier patients. Therefore, FH is assumed to function as a tumour suppressor. Mutations in genes encoding subunits of other TCAC enzyme SDH have also been reported recently in tumours: mutations in SDHB, SDHC, and SDHD genes predispose to paraganglioma and pheochromocytoma. In the present study, mutations in the SDHB gene were observed to predispose to RCC. This was the first time that mutations in SDHB have been detected in extra-paraganglial tumours. Two different SDHB mutations were observed in two unrelated families. In the first family, the index patient was diagnosed with RCC at the age of 24 years. Additionally, his mother with a paraganglioma (PGL) of the heart and his maternal uncle with lung cancer were both carriers of the mutation. The RCC of the index patient and the PGL of his mother showed LOH. In the other family, an SDHB mutation was detected in two siblings who were both diagnosed with RCC at the ages of 24 and 26 years. Both of the siblings also suffered PGL. All these tumours showed LOH. Therefore, we concluded that mutations in SDHB predispose also for RCC in certain families. Several tumour types were analysed for FH mutations to define the role of FH mutations in these tumour types. In addition, patients with a putative cancer phenotype were analysed to identify new HLRCC families. Three FH variants were detected, of which two were novel. One of the variants was observed in a patient diagnosed with ULMS at the age of 41 years. However, LOH was not detected in the tumour tissue. The FH enzyme activity of the mutated protein was clearly reduced, being 43% of the activity of the normal protein. Together with the results from an earlier study we calculated that the prevalence of FH mutations in Finnish non-syndromic ULMS is around 2.4%. Therefore, FH mutations seem to have a minor role in the pathogenesis on non-syndromic ULMS. Two other germline variants were detected in a novel tumour type, ovarian mucinous cystadenoma. However, tumour tissues of the patients were not available for LOH studies and therefore LOH status remained unclear. Therefore, it is possible that FH mutations predispose also for ovarian tumours but further studies are needed to verify this result. A novel variant form of the FH gene (FHv) was identified and characterized in more detail. FHv contains an alternative first exon (1b), which appeared to function as 5 UTR sequence. The translation of FHv is initiated in vitro from exons two and three. The localization of FHv is both cytosolic and nuclear, in contrast to the localization of FH in mitochondria. FHv is expressed at low levels in all human tissues. Interestingly, the expression was induced after heat shock treatment and in chronic hypoxia. Therefore, FHv might have a role e.g. in the adaptation to unfavourable growth conditions. However, this remains to be elucidated.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Chronic myeloid leukemia (CML) is a malignant clonal blood disease that originates from a pluripotent hematopoietic stem cell. The cytogenetic hallmark of CML, the Philadelphia chromosome (Ph), is formed as a result of reciprocal translocation between chromosomes 9 and 22, which leads to a formation of a chimeric BCR-ABL fusion gene. The BCR-ABL protein is a constitutively active tyrosine kinase that changes the adhesion properties of cells, constitutively activates mitogenic signaling, enhances cell proliferation and reduces apoptosis. This results in leukemic growth and the clinical disease, CML. With the advent of targeted therapies against the BCR-ABL fusion protein, the treatment of CML has changed considerably during the recent decade. In this thesis, the clinical significance of different diagnostic methods and new prognostic factors in CML have been assessed. First, the association between two different methods for measuring CML disease burden (the RQ-PCR and the high mitotic index metaphase FISH) was assessed in bone marrow and peripheral blood samples. The correlation between positive RQ-PCR and metaphase FISH samples was high. However, RQ-PCR was more sensitive and yielded measurable transcripts in 40% of the samples that were negative by metaphase FISH. The study established a laboratory-specific conversion factor for setting up the International Scale when standardizing RQ-PCR measurements. Secondly, the amount of minimal residual disease (MRD) after allogeneic hematopoietic stem cell transplantation (alloHSCT) was determined. For this, metaphase FISH was done for the bone marrow samples of 102 CML patients. Most (68%), had no residual cells during the entire follow-up time. Some (12 %) patients had minor (<1%) MRD which decreased even further with time, whereas 19% had a progressive rise in MRD that exceeded 1% or had more than 1% residual cells when first detected. Residual cells did not become eradicated spontaneously if the frequency of Ph+ cells exceeded 1% during follow-up. Next, the impact of deletions in the derivative chromosome 9, was examined. Deletions were observed in 15% of the CML patients who later received alloHSCT. After alloHSCT, there was no difference in the total relapse rate in patients with or without deletions. Nor did the estimates of overall survival, transplant-related mortality, leukemia-free survival and relapse-free time show any difference between these groups. When conventional treatment regimens are used, the der(9) status could be an important criterion, in conjunction with other prognostic factors, when allogeneic transplantation is considered. The significance of der(9) deletions for patients treated with tyrosine kinase inhibitors is not clear and requires further investigation. In addition to the der(9) status of the patient, the significance of bone marrow lymphocytosis as a prognostic factor in CML was assessed. Bone marrow lymphocytosis during imatinib therapy was a positive predictive factor and heralded optimal response. When combined with major cytogenetic response at three months of treatment, bone marrow lymphocytosis predicted a prognostically important major molecular response at 18 months of imatinib treatment. Although the validation of these findings is warranted, the determination of the bone marrow lymphocyte count could be included in the evaluation of early response to imatinib treatment already now. Finally, BCR-ABL kinase domain mutations were studied in CML patients resistant against imatinib treatment. Point mutations detected in the kinase domain were the same as previously reported, but other sequence variants, e.g. deletions or exon splicing, were also found. The clinical significance of the other variations remains to be determined.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The aim of this thesis was to develop measurement techniques and systems for measuring air quality and to provide information about air quality conditions and the amount of gaseous emissions from semi-insulated and uninsulated dairy buildings in Finland and Estonia. Specialization and intensification in livestock farming, such as in dairy production, is usually accompanied by an increase in concentrated environmental emissions. In addition to high moisture, the presence of dust and corrosive gases, and widely varying gas concentrations in dairy buildings, Finland and Estonia experience winter temperatures reaching below -40 ºC and summer temperatures above +30 ºC. The adaptation of new technologies for long-term air quality monitoring and measurement remains relatively uncommon in dairy buildings because the construction and maintenance of accurate monitoring systems for long-term use are too expensive for the average dairy farmer to afford. Though the documentation of accurate air quality measurement systems intended mainly for research purposes have been made in the past, standardised methods and the documentation of affordable systems and simple methods for performing air quality and emissions measurements in dairy buildings are unavailable. In this study, we built three measurement systems: 1) a Stationary system with integrated affordable sensors for on-site measurements, 2) a Wireless system with affordable sensors for off-site measurements, and 3) a Mobile system consisting of expensive and accurate sensors for measuring air quality. In addition to assessing existing methods, we developed simplified methods for measuring ventilation and emission rates in dairy buildings. The three measurement systems were successfully used to measure air quality in uninsulated, semi-insulated, and fully-insulated dairy buildings between the years 2005 and 2007. When carefully calibrated, the affordable sensors in the systems gave reasonably accurate readings. The spatial air quality survey showed high variation in microclimate conditions in the dairy buildings measured. The average indoor air concentration for carbon dioxide was 950 ppm, for ammonia 5 ppm, for methane 48 ppm, for relative humidity 70%, and for inside air velocity 0.2 m/s. The average winter and summer indoor temperatures during the measurement period were -7º C and +24 ºC for the uninsulated, +3 ºC and +20 ºC for the semi-insulated and +10 ºC and +25 ºC for the fully-insulated dairy buildings. The measurement results showed that the uninsulated dairy buildings had lower indoor gas concentrations and emissions compared to fully insulated buildings. Although occasionally exceeded, the ventilation rates and average indoor air quality in the dairy buildings were largely within recommended limits. We assessed the traditional heat balance, moisture balance, carbon dioxide balance and direct airflow methods for estimating ventilation rates. The direct velocity measurement for the estimation of ventilation rate proved to be impractical for naturally ventilated buildings. Two methods were developed for estimating ventilation rates. The first method is applicable in buildings in which the ventilation can be stopped or completely closed. The second method is useful in naturally ventilated buildings with large openings and high ventilation rates where spatial gas concentrations are heterogeneously distributed. The two traditional methods (carbon dioxide and methane balances), and two newly developed methods (theoretical modelling using Fick s law and boundary layer theory, and the recirculation flux-chamber technique) were used to estimate ammonia emissions from the dairy buildings. Using the traditional carbon dioxide balance method, ammonia emissions per cow from the dairy buildings ranged from 7 g day-1 to 35 g day-1, and methane emissions per cow ranged from 96 g day-1 to 348 g day-1. The developed methods proved to be as equally accurate as the traditional methods. Variation between the mean emissions estimated with the traditional and the developed methods was less than 20%. The developed modelling procedure provided sound framework for examining the impact of production systems on ammonia emissions in dairy buildings.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Screening of wastewater effluents from municipal and industrial wastewater treatment plants with biotests showed that the treated wastewater effluents possess only minor acute toxic properties towards whole organisms (e.g. bacteria, algae, daphnia), if any. In vitro tests (sub-mitochondrial membranes and fish hepatocytes) were generally more susceptible to the effluents. Most of the effluents indicated the presence of hormonally active compounds, as the production of vitellogenin, an egg yolk precursor protein, was induced in fish hepatocytes exposed to wastewater. In addition, indications of slight genotoxic potential was found in one effluent concentrate with a recombinant bacteria test. Reverse electron transport (RET) of mitochondrial membranes was used as a model test to conduct effluent assessment followed by toxicant characterisations and identifications. Using a modified U.S. EPA Toxicity Identification Evaluation Phase I scheme and additional case-specific methods, the main compound in a pulp and paper mill effluent causing RET inhibition was characterised to be an organic, relatively hydrophilic high molecular weight (HMW) compound. The toxicant could be verified as HMW lignin by structural analyses using nuclear magnetic resonance. In the confirmation step commercial and in-house extracted lignin products were used. The possible toxicity related structures were characterised by statistical analysis of the chemical breakdown structures of laboratory-scale pulping and bleaching effluents and the toxicities of these effluents. Finally, the biological degradation of the identified toxicant and other wastewater constituents was evaluated using bioassays in combination with chemical analyses. Biological methods have not been used routinely in establishing effluent discharge limits in Finland. However, the biological effects observed in this study could not have been predicted using only routine physical and chemical effluent monitoring parameters. Therefore chemical parameters cannot be considered to be sufficient in controlling effluent discharges especially in case of unknown, possibly bioaccumulative, compounds that may be present in small concentrations and may cause chronic effects.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recent epidemiological studies have shown a consistent association of the mass concentration of urban air thoracic (PM10) and fine (PM2.5) particles with mortality and morbidity among cardiorespiratory patients. However, the chemical characteristics of different particulate size ranges and the biological mechanisms responsible for these adverse health effects are not well known. The principal aims of this thesis were to validate a high volume cascade impactor (HVCI) for the collection of particulate matter for physicochemical and toxicological studies, and to make an in-depth chemical and source characterisation of samples collected during different pollution situations. The particulate samples were collected with the HVCI, virtual impactors and a Berner low pressure impactor in six European cities: Helsinki, Duisburg, Prague, Amsterdam, Barcelona and Athens. The samples were analysed for particle mass, common ions, total and water-soluble elements as well as elemental and organic carbon. Laboratory calibration and field comparisons indicated that the HVCI can provide a unique large capacity, high efficiency sampling of size-segregated aerosol particles. The cutoff sizes of the recommended HVCI configuration were 2.4, 0.9 and 0.2 μm. The HVCI mass concentrations were in a good agreement with the reference methods, but the chemical composition of especially the fine particulate samples showed some differences. This implies that the chemical characterization of the exposure variable in toxicological studies needs to be done from the same HVCI samples as used in cell and animal studies. The data from parallel, low volume reference samplers provide valuable additional information for chemical mass closure and source assessment. The major components of PM2.5 in the virtual impactor samples were carbonaceous compounds, secondary inorganic ions and sea salt, whereas those of coarse particles (PM2.5-10) were soil-derived compounds, carbonaceous compounds, sea salt and nitrate. The major and minor components together accounted for 77-106% and 77-96% of the gravimetrically-measured masses of fine and coarse particles, respectively. Relatively large differences between sampling campaigns were observed in the organic carbon content of the PM2.5 samples as well as the mineral composition of the PM2.5-10 samples. A source assessment based on chemical tracers suggested clear differences in the dominant sources (e.g. traffic, residential heating with solid fuels, metal industry plants, regional or long-range transport) between the sampling campaigns. In summary, the field campaigns exhibited different profiles with regard to particulate sources, size distribution and chemical composition, thus, providing a highly useful setup for toxicological studies on the size-segregated HVCI samples.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Volatile organic compounds (VOCs) have a great influence on tropospheric chemistry; they affect ozone formation and they or their reaction products are able to take part in secondary organic aerosol formation; some of the VOCs are themselves toxic. Knowing the concentrations and sources of different reactive volatile organic compounds is essential for the development of ozone control strategies and for studies of secondary organic aerosol formation. The objective of this work was to study volatile organic compounds in urban air, develop and validate determination methods for them, characterize their concentrations and estimate the contributions of different VOC sources. Of the different compound groups detected in the urban air of Helsinki, alkanes were found to have the highest concentrations, but when the concentrations were scaled against the reactivity with hydroxyl radicals (OH), aromatic hydrocarbons and alkenes were found to have the greatest effect on local chemistry. Comparisons with rural sites showed that concentrations at Utö and Hyytiälä were generally lower than those in Helsinki, especially for the alkenes and aromatic hydrocarbons, but concentrations of halogenated hydrocarbons at Utö and carbonyls at Hyytiälä were at the same level as in Helsinki. Most halogenated hydrocarbons do not have any significant sources in Helsinki, and carbonyls are formed in the atmosphere in the reactions of other VOCs, and are therefore also produced in other than urban areas. At Hyytiälä carbonyls were found to have an important role in the local chemistry. The contribution of carbonyls as an OH sink was higher than that of the monoterpenes and aromatic hydrocarbons. Based on the emission profile and concentration measurements, the contributions of different sources were estimated at urban (Helsinki) and residential (Järvenpää) sites using a chemical mass balance (CMB) receptor model. It was shown that it is possible to apply CMB in the case of a large number of different compounds with different properties. According to the CMB analysis, the major sources for these VOCs in Helsinki were traffic and distant sources. At the residential site in Järvenpää, the contribution due to traffic was minor, while distant sources, liquid gasoline and wood combustion made higher contributions. It was also shown that wood combustion can be an important source at some locations of VOCs usually considered as traffic-related compounds (e.g., benzene).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Elucidating the mechanisms responsible for the patterns of species abundance, diversity, and distribution within and across ecological systems is a fundamental research focus in ecology. Species abundance patterns are shaped in a convoluted way by interplays between inter-/intra-specific interactions, environmental forcing, demographic stochasticity, and dispersal. Comprehensive models and suitable inferential and computational tools for teasing out these different factors are quite limited, even though such tools are critically needed to guide the implementation of management and conservation strategies, the efficacy of which rests on a realistic evaluation of the underlying mechanisms. This is even more so in the prevailing context of concerns over climate change progress and its potential impacts on ecosystems. This thesis utilized the flexible hierarchical Bayesian modelling framework in combination with the computer intensive methods known as Markov chain Monte Carlo, to develop methodologies for identifying and evaluating the factors that control the structure and dynamics of ecological communities. These methodologies were used to analyze data from a range of taxa: macro-moths (Lepidoptera), fish, crustaceans, birds, and rodents. Environmental stochasticity emerged as the most important driver of community dynamics, followed by density dependent regulation; the influence of inter-specific interactions on community-level variances was broadly minor. This thesis contributes to the understanding of the mechanisms underlying the structure and dynamics of ecological communities, by showing directly that environmental fluctuations rather than inter-specific competition dominate the dynamics of several systems. This finding emphasizes the need to better understand how species are affected by the environment and acknowledge species differences in their responses to environmental heterogeneity, if we are to effectively model and predict their dynamics (e.g. for management and conservation purposes). The thesis also proposes a model-based approach to integrating the niche and neutral perspectives on community structure and dynamics, making it possible for the relative importance of each category of factors to be evaluated in light of field data.