16 resultados para rearing apparatus

em Helda - Digital Repository of University of Helsinki


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Vasikoiden kasvatus yksilökarsinoissa, imemismahdollisuuden puute maitojuoton yhteydessä sekä pienet juomamäärät ovat tekijöitä, jotka mahdollisesti voivat vähentää vasikoiden hyvinvointia. Vasikoiden kasvatukseen etsitäänkin uusia tapoja, joissa eläinten käyttäytymistarpeet ja hyvinvointi otetaan entistä paremmin huomioon. Tässä väitöskirjassa vasikoiden kasvatusta on tarkasteltu sekä tuotannon että vasikoiden käyttäytymisen ja hyvinvoinnin kannalta. Väitöskirja koostuu kolmesta kokeesta, joista ensimmäisessä tutkittiin vasikoiden kasvatusta ryhmäkarsinoissa ulkona tai sisällä ja vasikoiden kasvatusta sisällä ryhmä- tai yksilökarsinoissa. Toisessa kokeessa vasikoiden annettiin imeä emiään rajoitetusti lypsyn jälkeen viiden tai kahdeksan viikon ajan ja kolmannessa selvitettiin vasikoiden veden juontia, kun vasikat saivat juomarehua vapaasti. Lisäksi kokeiden yhdistetystä aineistosta analysoitiin eri rehujen syöntimäärien suhdetta sekä rehujen vaikutusta kasvuun ennen ja jälkeen maidosta vieroituksen. Tutkimuksessa todettiin, että vasikoita voi ryhmässä kasvattaa kylmissä ja vaihtelevissa sääoloissa ulkona, kunhan ne hoidetaan ja ruokitaan erittäin huolellisesti. Kylmällä ilmalla vasikat saattavat kuitenkin syödä väkirehua vähemmän varsinkin, jos ruokailupaikka on ulkona ja makuualue sisällä. Ryhmässä kasvaneet vasikat aloittivat sekä kuivien rehujen syönnin että märehtimisen nuorempina kuin yksilökarsinassa kasvaneet. Ryhmissä esiintyvää käyttäytymisongelmaa, toisten vasikoiden imemistä, voidaan vähentää hoito- ja ruokintamenetelmillä. Annettaessa vasikoiden imeä emiään rajoitetusti lypsyn jälkeen vasikat oppivat imemään emiään hyvin nopeasti. Lypsytyö vaikeutui muutamien lehmien kohdalla, sillä ne pidättivät maitoa lypsettäessä. Saadessaan imeä rajoitetusti vasikat imivät suurehkoja maitomääriä kerrallaan. Vieroittaminen suurilta maitomääriltä viiden viikon iässä oli kuitenkin liian aikaista, koska vasikat eivät vielä syöneet riittävästi kuivia rehuja. Vieroitus emästä niin viiden kuin kahdeksankin viikon iässä aiheutti vasikoissa levottomuutta ja ääntelyn lisääntymistä. Saadessaan hapatettua juomarehua vapaasti vasikat joivat keskimäärin vain vähän vettä, olipa vesilähteenä avoin ämpäri tai vesinippa. Vasikoiden välillä oli suurta vaihtelua veden juontimäärissä. Viikkoa ennen maidosta vieroitusta vasikat joivat 0-3 l vettä päivässä. Vasikat joivat nipasta kerrallaan vähemmän vettä kuin ämpäristä, ja käyttivät enemmän aikaa päivässä veden juomiseen kuin vesiämpäristä juoneet vasikat. Suurin osa vasikoista joi vettä juomanipoista erikoisella tavalla esimerkiksi painamalla nippaa otsalla ja juomalla tippuvaa vettä. Vesinipat voivat olla siis vasikoille joko vaikeita tai epämukavia käyttää. Vasikoiden juoman maitomäärän lisääntyessä kasvu lisääntyy selvästi. Runsas maidon juominen vähentää kuitenkin kuivien rehujen syöntiä ja vieroitusvaiheessa kasvu voi hidastua. Vasikat olisikin tärkeää vieroittaa vähitellen, ettei muutoksia kasvuun tulisi. Syönti- ja kasvutulokset eivät aina anna oikeaa kuvaa kasvatusmenetelmien eroista eläinten hyvinvoinnin kannalta. Käyttäytyminen on herkkä hyvinvoinnin mittari ja se tulisikin aina huomioida eri kasvatusmenetelmiä arvioitaessa. .

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The endoplasmic reticulum (ER) and the Golgi apparatus are organelles that produce, modify and transport proteins and lipids and regulate Ca2+ environment within cells. Structurally they are composed of sheets and tubules. Sheets may take various forms: intact, fenestrated, single or stacked. The ER, including the nuclear envelope, is a single continuous network, while the Golgi shows only some level of connectivity. It is often unclear, how different morphologies correspond to particular functions. Previous studies indicate that the structures of the ER and Golgi are dynamic and regulated by fusion and fission events, cytoskeleton, rate of protein synthesis and secretion, and specific structural proteins. For example, many structural proteins shaping tubular ER have been identified, but sheet formation is much more unclear. In this study, we used light and electron microscopy to study morphological changes of the ER and Golgi in mammalian cells. The proportion, type, location and dynamics of ER sheets and tubules were found to vary in a cell type or cell cycle stage dependent manner. During interphase, ER and Golgi structures were demonstrated to be regulated by p37, a cofactor of the fusion factor p97, and microtubules, which also affected the localization of the organelles. Like previously shown for the Golgi, the ER displayed a tendency for fenestration and tubulation during mitosis. However, this shape change did not result in ER fragmentation as happens to Golgi, but a continuous network was retained. The activity of p97/p37 was found to be important for the reassembly of both organelles after mitosis. In EM images, ER sheet membranes appear rough, since they contain attached ribosomes, whereas tubular membranes appear smooth. Our studies revealed that structural changes of the ER towards fenestrated and tubular direction correlate with loss of ER-bound ribosomes and vice versa. High and low curvature ER membranes have a low and high density of ribosomes, respectively. To conclude, both ER and Golgi architecture depend on fusion activity of p97/p37. ER morphogenesis, particularly of the sheet shape, is intimately linked to the density of membrane bound ribosomes.

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In this dissertation, I present an overall methodological framework for studying linguistic alternations, focusing specifically on lexical variation in denoting a single meaning, that is, synonymy. As the practical example, I employ the synonymous set of the four most common Finnish verbs denoting THINK, namely ajatella, miettiä, pohtia and harkita ‘think, reflect, ponder, consider’. As a continuation to previous work, I describe in considerable detail the extension of statistical methods from dichotomous linguistic settings (e.g., Gries 2003; Bresnan et al. 2007) to polytomous ones, that is, concerning more than two possible alternative outcomes. The applied statistical methods are arranged into a succession of stages with increasing complexity, proceeding from univariate via bivariate to multivariate techniques in the end. As the central multivariate method, I argue for the use of polytomous logistic regression and demonstrate its practical implementation to the studied phenomenon, thus extending the work by Bresnan et al. (2007), who applied simple (binary) logistic regression to a dichotomous structural alternation in English. The results of the various statistical analyses confirm that a wide range of contextual features across different categories are indeed associated with the use and selection of the selected think lexemes; however, a substantial part of these features are not exemplified in current Finnish lexicographical descriptions. The multivariate analysis results indicate that the semantic classifications of syntactic argument types are on the average the most distinctive feature category, followed by overall semantic characterizations of the verb chains, and then syntactic argument types alone, with morphological features pertaining to the verb chain and extra-linguistic features relegated to the last position. In terms of overall performance of the multivariate analysis and modeling, the prediction accuracy seems to reach a ceiling at a Recall rate of roughly two-thirds of the sentences in the research corpus. The analysis of these results suggests a limit to what can be explained and determined within the immediate sentential context and applying the conventional descriptive and analytical apparatus based on currently available linguistic theories and models. The results also support Bresnan’s (2007) and others’ (e.g., Bod et al. 2003) probabilistic view of the relationship between linguistic usage and the underlying linguistic system, in which only a minority of linguistic choices are categorical, given the known context – represented as a feature cluster – that can be analytically grasped and identified. Instead, most contexts exhibit degrees of variation as to their outcomes, resulting in proportionate choices over longer stretches of usage in texts or speech.

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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.

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The repair of corneal wounds requires both epithelial cell adhesion and migration. Basement membrane (BM) and extracellular matrix (ECM) proteins function in these processes via integrin and non-integrin receptors. We have studied the adhesion, spreading and migration of immortalized human corneal epithelial (HCE) cells and their interactions with the laminins (Lms), fibronectins and tenascins produced. Human corneal BM expresses Lms-332 and -511, while Lm-111 was not found in these experiments. HCE cells produced both processed and unprocessed Lm-332, whereas neither Lm-111 nor Lm-511 was produced. Because HCE cells did not produce Lm-511, although it was present in corneal BM, we suggest that Lm-511 is produced by stromal keratocytes. The adhesion of HCE cells to Lms-111, -332 and -511 was studied first by determining the receptor composition of HCE cells and then by using quantitative cell adhesion assays. Immunofluorescence studies revealed the presence of integrin α2, α3, α6, β1 and β4 subunits. Among the non-integrin receptors, Lutheran (Lu) was found on adhering HCE cells. The cells adhered via integrin α3β1 to both purified human Lms-332 and -511 as well as to endogenous Lm-332. However, only integrin β1 subunit functioned in HCE cell adhesion to mouse Lm-111. The adhesion of HCE cells to Lm-511 was also mediated by Lu. Since Lm-511 did not induce Lu into focal adhesions in HCE cells, we suggest that Lm-511 serves as an ECM ligand enabling cell motility. HCE cells produced extradomain-A fibronectin, oncofetal fibronectin and tenascin-C (Tn-C), which are also found during corneal wound healing. Monoclonal antibodies (MAbs) against integrins α5β1 and αvβ6 as well as the arginine-glycine-aspartic acid (RGD) peptide inhibited the adhesion of HCE cells to fibronectin. Although the cells did not adhere to Tn-C, they adhered to the fibronectin/Tn-C coat and were then more efficiently inhibited by the function-blocking MAbs and RGD peptide. During the early adhesion, HCE cells codeposited Lm-332 and the large subunit of tenascin-C (Tn-CL) beneath the cells via the Golgi apparatus and microtubules. Integrin β4 subunit, which is a hemidesmosomal component, did not mediate the early adhesion of HCE cells to Lm-332 or Lm-332/Tn-C. Based on these results, we suggest that the adhesion of HCE cells is initiated by Lm-332 and modulated by Tn-CL, as it has been reported to prevent the assembly of hemidesmosomes. Thereby, Tn-CL functions in the motility of HCE cells during wound healing. The different distribution of processed and unprocessed Lm-332 in adhering, spreading and migrating HCE cells suggests a distinct role for these isoforms. We conclude that the processed Lm-332 functions in cell adhesion, whereas the unprocessed Lm-332 participates in cell spreading and migration.

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Pectobacterium atrosepticum on Gram-negatiivinen bakteeri, joka aiheuttaa perunan tyvi- ja märkämätää. P. atrosepticum bakteerin optimilämpötila on melko alhainen ja se on yleinen lauhkeilla alueilla. Tyvimätä leviää pääasiassa siemenperunan välityksellä ja siksi se on ongelma erityisesti siemenperunan tuotannossa. P. atrosepticum kannan SCRI1043 genomi on julkaistu ja sitä tutkitaan malliorganismina märkä- ja tyvimädän taudinaiheuttamisen ymmärtämiseksi. Tämä opportunistinen taudinaiheuttaja voi elää isäntäkasvissa kuukausia piilevänä, aiheuttamatta näkyviä oireita. Suotuisissa olosuhteissa bakteerit alkavat jakautua ja tuottaa kasvin kudoksia hajottavia entsyymejä. Mädäntyvä kasvimassa tarjoaa ravinteita bakteerien kasvuun ja mahdollistaa isäntäkasvin asuttamisen. Soluseiniä hajottavien entsyymien merkitys taudinaiheuttamisessa on hyvin tunnettu, mutta oireettomasta jaksosta ja taudin alkuvaiheista tiedätään vain vähän. Bakteerin genomi sisältää monia toksiineja, adhesiineja, hemolysiineja ja muita proteiineja, joilla saattaa olla merkitys taudinaiheuttamisessa. Tässä työssä käytettiin proteomiikkaa ja mikrosiruanalysiä P. atrosepticum bakteerin erittyvien proteiinien ja geeniekspression tutkimiseen. Proteiinit, jotka eritetään ulos bakteerista, toimivat todennäköisesti taudinaiheuttamisessa, koska ne ovat suorassa kontaktissa isäntäkasvin kanssa. Analyysit suoritettiin olosuhteissa, jotka muistuttavat kasvin soluvälitilaa: matala pH, vähän ravinteita ja matala lämpötila. Isäntäkasvin läsnäolon vaikutusta proteiinien tuottoon ja geeniekspressioon tutkittiin lisäämällä perunauutetta kasvatusalustaan. Tutkimuksessa tunnistettiin P. atrosepticum bakteerin monia jo tunnettuja ja mahdollisesti taudinaiheuttamiseen liittyviä proteiineja. Perunauute lisäsi hiljattain tunnistetun, proteiinien eritysreittiä (tyyppi VI sekreetio, T6SS) koodaavien geenien ilmentymistä. Lisäksi bakteerin havaittiin erittävän useita T6SS:n liittyviä proteiineja kasvualustaan, johon oli lisätty perunauutetta. T6SS:n merkitys bakteereille on vielä epäselvä ja sen vaikutuksesta taudinaiheuttamiseen on julkaistu ristiriitaisia tuloksia. Märkä- ja tyvimädän ymmärtäminen molekulaarisella tasolla luo pohjan tautien kontrollointiin tähtäävään soveltavaan tutkimukseen. Tämä tutkimus lisää tietoa kasvi-patogeeni- interaktiosta ja sitä voidaan tulevaisuudessa käyttää hyväksi esimerkiksi diagnostiikassa, resistenttien perunalajikkeiden jalostuksessa tai viljely- ja varastointiolosuhteiden parantamisessa.

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In this thesis, the kinetics of several alkyl, halogenated alkyl, and alkenyl free radical reactions with NO2, O2, Cl2, and HCl reactants were studied over a wide temperature range in time resolved conditions. Laser photolysis photoionisation mass spectrometer coupled to a flow reactor was the experimental method employed and this thesis present the first measurements performed with the experimental system constructed. During this thesis a great amount of work was devoted to the designing, building, testing, and improving the experimental apparatus. Carbon-centred free radicals were generated by the pulsed 193 or 248 nm photolysis of suitable precursors along the tubular reactor. The kinetics was studied under pseudo-first-order conditions using either He or N2 buffer gas. The temperature and pressure ranges employed were between 190 and 500 K, and 0.5 45 torr, respectively. The possible role of heterogeneous wall reactions was investigated employing reactor tubes with different sizes, i.e. to significantly vary the surface to volume ratio. In this thesis, significant new contributions to the kinetics of carbon-centred free radical reactions with nitrogen dioxide were obtained. Altogether eight substituted alkyl (CH2Cl, CHCl2, CCl3, CH2I, CH2Br, CHBr2, CHBrCl, and CHBrCH3) and two alkenyl (C2H3, C3H3) free radical reactions with NO2 were investigated as a function of temperature. The bimolecular rate coefficients of all these reactions were observed to possess negative temperature dependencies, while pressure dependencies were not noticed for any of these reactions. Halogen substitution was observed to moderately reduce the reactivity of substituted alkyl radicals in the reaction with NO2, while the resonance stabilisation of the alkenyl radical lowers its reactivity with respect to NO2 only slightly. Two reactions relevant to atmospheric chemistry, CH2Br + O2 and CH2I + O2, were also investigated. It was noticed that while CH2Br + O2 reaction shows pronounced pressure dependence, characteristic of peroxy radical formation, no such dependence was observed for the CH2I + O2 reaction. Observed primary products of the CH2I + O2 reaction were the I-atom and the IO radical. Kinetics of CH3 + HCl, CD3 + HCl, CH3 + DCl, and CD3 + DCl reactions were also studied. While all these reactions possess positive activation energies, in contrast to the other systems investigated in this thesis, the CH3 + HCl and CD3 + HCl reactions show a non-linear temperature dependency on the Arrhenius plot. The reactivity of substituted methyl radicals toward NO2 was observed to increase with decreasing electron affinity of the radical. The same trend was observed for the reactions of substituted methyl radicals with Cl2. It is proposed that interactions of frontier orbitals are responsible to these observations and Frontier Orbital Theory could be used to explain the observed reactivity trends of these highly exothermic reactions having reactant-like transition states.

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The knowledge about the optimal rearing conditions, such as water temperature and quality, photoperiod and density, with the understanding of animal nutritional requirements forms the basis of economically stable aquaculture for freshwater crayfish. However, the shift from a natural environment to effective culture conditions induces several changes, not only at the population level, but also at the individual level. The social contacts between conspecifics increase with increasing animal density. The competition for limited resources (e.g. food, shelter, mates) is more severe with the presence of agonistic behaviour and may lead to unequal distribution of these. The objectives of this study were to: 1) study the distribution of a common food resource between communally reared signal crayfish (Pacifastacus leniusculus) and to assign potential feeding hierarchy on the basis of individual food intake measurements, 2) explore the possibilities of size distribution manipulations to affect population dynamics and food intake to improve growth and survival in culture and 3) study the effect of food ration and spatial distribution on food intake and to explore the effect of temperature and food ration on growth and body composition of freshwater crayfish. The feeding ranks between animals were assigned with a new method for individual food intake measurement of communally reared crayfish. This technique has a high feasibility and a great potential to be applied in crayfish aquaculture studies. In this study, signal crayfish showed high size-related variability in food consumption both among individuals within a group (inter-individual) and within individual day-to-day variation (intra-individual). Increased competition for food led to an unequal distribution of this resource and this may be a reason for large growth differences between animals. The consumption was significantly higher when reared individually in comparison with communal housing. These results suggest that communally housed crayfish form a feeding hierarchy and that the animal size is the major factor controlling the position in this hierarchy. The optimisation of the social environment ( social conditions ) was evaluated in this study as a new approach to crayfish aquaculture. The results showed that the absence of conspecifics (individual rearing vs. communal housing) affects growth rate, food intake and the proportion of injured animals, whereas size variation between animals influences the number and duration of agonistic encounters. In addition, animal size had a strong influence on the fighting success of signal crayfish reared in a social milieu with a wide size variation of conspecifics. Larger individuals initiated and won most of the competitions, which suggests size-based social hierarchy of P. leniusculus. This is further supported by the fact that the length and weight gain of smaller animals increased after size grading, maybe because of a better access to the food resource due to diminished social pressure. However, the high dominance index was not based on size under conditions of limited size variation, e.g. those characteristic of restocked natural populations and aquaculture, indicating the important role of behaviour on social hierarchy.

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Many Gram-negative bacteria pathogenic to plants and animals possess type III secretion systems that are used to cause disease. Effector proteins are injected into host cells using the type III secretion machineries. Despite vigorous studies, the nature of the secretion signal for type III secreted proteins still remains elusive. Both mRNA and proteinaceous signals have been proposed. Findings on coupling of translation to secretion by the type III secretion systems are also still contradictory. This study dealt with the secretion signal of HrpA from Pseudomonas syringae pathovar tomato. HrpA is the major component of the type III secretion system-associated Hrp pilus and a substrate for the type III secretion systems. The secretion signal was shown to reside in the first 15 codons or amino acids, a location typical for type III secretion signals. Translation of HrpA in the absence of a functional type III secretion system was established, but it does not exclude the possibility of coupling of translation to secretion when the secretion apparatus is present. The hrpA transcripts from various unrelated plant pathogenic bacteria were shown to be extremely stable. The biological relevance of this observation is unknown, but possible explanations include the high prevalence of HrpA protein, an mRNA secretion signal or timing of secretion. The hrpA mRNAs are stable over a wide range of temperatures, in the absence of translating ribosomes and even in the heterologous host Escherichia coli. The untranslated regions (UTRs) of hrpA transcripts from at least 20 pathovars of Pseudomonas syringae are highly homologous, whilst their coding regions exhibit low similarity. The stable nature of hrpA messenger RNAs is likely to be due to the folding of their 5 and 3 UTRs. In silico the UTRs seem to form stem-loop structures, the hairpin structures in the 3 UTRs being rich in guanidine and cytosine residues. The stable nature of the hrpA transcript redirected the studies to the stabilization of heterologous transcripts and to the use of stable messenger RNAs in recombinant protein production. Fragments of the hrpA transcript can be used to confer stability on heterologous transcripts from several sources of bacterial and eukaryotic origin, and to elevate the levels of production of the corresponding recombinant proteins several folds. hrpA transcript stabilizing elements can be used for improving the yields of recombinant proteins even in Escherichia coli, one of the most commonly used industrial protein production hosts.

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Wild salmon stocks in the northern Baltic rivers became endangered in the second half of the 20th century, mainly due to recruitment overfishing. As a result, supplementary stocking was widely practised, and supplementation of the Tornionjoki salmon stock took place over a 25 year period until 2002. The stock has been closely monitored by electrofishing, smolt trapping, mark-recapture studies, catch samples and catch surveys. Background information on hatchery-reared stocked juveniles was also collected for this study. Bayesian statistics was applied to the data as this method offers the possibility of bringing prior information into the analysis and an advanced ability for incorporating uncertainty, and also provides probabilities for a multitude of hypotheses. Substantial divergences between reared and wild Tornionjoki salmon were identified in both demographic and phenological characteristics. The divergences tended to be larger the longer the duration spent in hatchery and the more favourable the hatchery conditions were for fast growth. Differences in environment likely induced most of the divergences, but selection of brood fish might have resulted in genotypic divergence in maturation age of reared salmon. Survival of stocked 1-year old juveniles to smolt varied from about 10% to about 25%. Stocking on the lower reach of the river seemed to decrease survival, and the negative effect of stocking volume on survival raises the concern of possible similar effects on the extant wild population. Post-smolt survival of wild Tornionjoki smolts was on average two times higher than that of smolts stocked as parr and 2.5 times higher than that of stocked smolts. Smolts of different groups showed synchronous variation and similar long-term survival trends. Both groups of reared salmon were more vulnerable to offshore driftnet and coastal trapnet fishing than wild salmon. Average survival from smolt to spawners of wild salmon was 2.8 times higher than that of salmon stocked as parr and 3.3 times higher than that of salmon stocked as smolts. Wild salmon and salmon stocked as parr were found to have similar lifetime survival rates, while stocked smolts have a lifetime survival rate over 4 times higher than the two other groups. If eggs are collected from the wild brood fish, stocking parr would therefore not be a sensible option. Stocking smolts instead would create a net benefit in terms of the number of spawners, but this strategy has serious drawbacks and risks associated with the larger phenotypic and demographic divergences from wild salmon. Supplementation was shown not to be the key factor behind the recovery of the Tornionjoki and other northern Baltic salmon stocks. Instead, a combination of restrictions in the sea fishery and simultaneous occurrence of favourable natural conditions for survival were the main reasons for the revival in the 1990 s. This study questions the effectiveness of supplementation as a conservation management tool. The benefits of supplementation seem at best limited. Relatively high occurrences of reared fish in catches may generate false optimism concerning the effects of supplementation. Supplementation may lead to genetic risks due to problems in brood fish collection and artificial rearing with relaxed natural selection and domestication. Appropriate management of fisheries is the main alternative to supplementation, without which all other efforts for long-term maintenance of a healthy fish resource fail.

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Predation forms one of the main selective forces in nature and in a vast number of prey species the behavioural responses form the main way to avoid predation. World wide numerous captive breeding programs are used to produce fish and other animal species for conservational reintroductions. However, rearing animals in the absence of predators in captivity has been shown to weaken their predator avoidance skills and lead to behavioural divergence between wild and captive-bred populations. In my thesis I studied the effects of predator odour exposures on antipredator behavioural and physiological responses of captive reared Saimaa Arctic charr. This charr population is the most endangered fish population in Finland and a sample of the remaining population has been taken to captive breeding and used for an extensive reintroduction program. Lowered responsiveness to predators is probably one of the major reasons for the poor survival probability of the charr after release into the wild. The main aims of my thesis were to explore the reasons for behavioural phenotypic variation in this charr population and whether naïve charr young could be trained to recognise their natural predators. The predator species in my thesis were burbot (Lota lota) and pikeperch (Sander lucioperca). In my thesis I showed that the captive-bred charr responded to chemical cues from burbot and pikeperch, but the magnitude of responses was linked to the predator species. The burbot odour increased the spatial odour avoidance of the charr young. On the other hand, in the pikeperch treatment charr reduced their relative swimming activity and tended to show more freezing behaviour relative to the burbot treatment. It seems evident that these different responses are related to the different hunting tactics of predator species. Furthermore, I detected wide between-family differences in antipredator responsiveness (i.e. inherited variation in antipredator behaviours) in this captive stock. Detected differences were greater in the response towards burbot than towards pikeperch. These results, in addition to predator-specific antipredator responses, suggest that there is a clear inherited component in antipredator responsiveness in Saimaa charr population and that the detected inherited differences could explain a part of the behavioural phenotypic variation in this population. In my thesis I also found out that both social learning and direct exposure to live predators enhance the antipredator responsiveness of charr young. In addition, I obtained indications that predator odour exposures (i.e. life-skills training) in alevin and fry stages can fine-tune the innate antipredator responsiveness of charr. Thus, all these methods have the potential to enhance the innate antipredator responsiveness of naïve charr young, possibly also improving the post-release survival of these trained individuals in the wild. However, the next logical phase would be to carry out large scale survival studies in the wild to test this hypothesis. Finally, the results of my thesis emphasize that possible long-term life-skills training methods should take into account not only the behavioural but also the physiological effects of training.

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The modern unilateral surgical treatment of otosclerosis started in 1956. Simultaneous bilateral surgery has not been reported in stapes surgery and in case of bilateral otosclerosis ears are operated in two different sessions. Simultaneous surgery would give the patient the opportunity to gain advantages of bilateral hearing within one session, with less time spent in hospital and on sick leave. The mechanism for vestibular symptoms and the exact end organ affected after surgery is still unveiled. This thesis presents the results of experimental simultaneous bilateral stapes surgery, and vestibular symptoms and findings before and after unilateral stapes surgery. In addition, we explore reasons for outpatient failures in otosclerosis surgery. -- Study I examines the outcome of simultaneous bilateral surgery. Hearing was evaluated with standard pure tone and speech audiograms and vestibular apparatus with visual feedback posturography (VFP) during the one-year follow-up. Subjective symptoms and quality of life were assessed with questionnaires. In study II, reasons for outpatient failures in stapes surgery were explored. Forty-seven consecutive stapedotomies and stapedectomies performed by the same surgeon were included, and the effect of failures on hearing results were analysed. Vestibular symptoms and the end organ(s) affected after stapes surgery were investigated in studies III and IV. With video-oculography (VOG), nystagmus was measured preoperatively, and at one week, one month and 3 months postoperatively in the first phase (III). In the second phase (IV), recordings were obtained some hours postoperatively. The hearing results of the simultaneous bilateral surgery were comparable with unilateral surgeries reported. Recovery from the surgery was fast. Significant improvement in performance and quality of life was noted already month after operation in subjective evaluations. Based on these results, simultaneous bilateral surgery is a suitable approach in bilateral otosclerosis Significantly more outpatient failures occurred for medical reasons in the stapedectomy group (13%) than in the stapedotomy group (2%). Stapedotomy should be favoured if outpatient surgery is planned. However, unplanned admission did not worsen the prognosis. VOG measurements in study III did not show any specific type of nystagmus in patients having vestibular symptoms postoperatively. However, VOG measurements immediately after surgery (IV) revealed nystagmus consistent with a minor disturbance of the semicircular canals in 33% of the patients. Subjectively, half of the patients reported vestibular symptoms that were probably of diverse origin, and could have originated from both otolith and semicircular canal parts of the vestibular organ. Since vestibular symptoms and signs are mild, patients may be safely discharged some hours after stapes surgery.

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Discursive Matrixes of Motherhood examines women's discourse on their experiences of new motherhood in Finland and France. It sets out from two culturally prevalent turns of speech observed in different social forums: in conversations amongst mothers with tertiary education and in the print media. The pool of data includes: 30 interviews, 8 autobiographically inspired novels and 80 items from women's magazines. With instruments loaned from the toolbox of rhetorical analysis, the recurrence of certain expressions or clichés is analyzed with regard to the national, cultural, biographical, political and daily contexts and settings in which the speaking subjects are immersed. "Staying at home is such a short and special time", the first expression under scrutiny, caught the sociological eye because of its salience in Finland and because it appeared as contradictory with a core characteristic of the Finnish context:long family leave. The cliché was found to function as a discursive micromechanism which swept mothers' 'complaints' under the proverbial carpet. Proper emotions and decency in mother-talk thereby appear as collective achievements. An opposite phenomenon - that of the scaling up of rewards procured by children - was also discerned in the data. Indeed, the French expression "Profiter de mon enfant" ["making the most of my child"/"enjoying my child"] is interpreted as a crystallization of a hedonist ethos of motherhood in everyday language. Secondly, the recurrence of this utterance is analyzed in the light of a requisite located in child-rearing expert literature: that of pleasure that women should take in mothering. Hence, one of the rules found to structure the discursive matrixes of motherhood is the laudability and audibility of enjoyment and conversely the discretion and discouragement of 'complaints'. The cultivation of decent matches between certain categories of emotions and certain categories of individuals also appears as a characteristic of discursive matrixes. One of the methodological findings relates to the fact that such matches may be constituted as sociological objects through the identification of recurrent discursive crystallizations in a given culture. Ideal matches may crystallize in turns of speech and mismatches can be managed through clichés. Becoming a mother entails an immersion in such a particular economy of speech. Key words: mothers, motherhood, transition to parenthood, family, emotions, morality, bonds, rhetorical analysis, discourse analysis, media analysis, France, Finland, comparative sociology

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The status of the TOTEM experiment is described as well as the prospects for the measurements in the early LHC runs. The primary goal of TOTEM is the measurement of the total p-p cross section, using a method independent of the luminosity. A final accuracy of 1% is ex- pected with dedicated β∗ = 1540 m runs, while at the beginning a 5% resolution is achievable with a β∗ = 90 m optics. Accordingly to the running scenarios TOTEM will be able to measure the elastic scattering in a wide range of t and to study the cross-sections and the topologies of diffractive events. In a later stage, physics studies will be extended to low-x and forward physics collaborating with CMS as a whole experimental apparatus.

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Väärinkäytettyjen aineiden seulontaan käytetyn menetelmän tulee olla herkkä, selektiivinen, yksinkertainen, nopea ja toistettava. Työn tavoitteena oli kehittää yksinkertainen, mutta herkkä, esikäsittelymenetelmä bentsodiatsepiinien ja amfetamiinijohdannaisten kvalitatiiviseen seulomiseen virtsasta mikropilarisähkösumutussirun (μPESI) avulla, mikä tarjoaisi vaihtoehdon seulonnassa käytetyille immunologisille menetelmille, joiden herkkyys ja selektiivisyys ovat puutteellisia. Tavoitteena oli samalla tarkastella mikropilarisähkösumutussirun toimivuutta biologisten näytteiden analyysissa. Esikäsittely optimoitiin erikseen bentsodiatsepiineille ja amfetamiinijohdannaisille. Käytettyjä esikäsittelymenetelmiä olivat neste-nesteuutto, kiinteäfaasiuutto Oasis HLB-patruunalla ja ZipTip®-pipetinkärjellä sekä laimennus ja suodatus ilman uuttoa. Mittausten perusteella keskityttiin optimoimaan ZipTip®-uuttoa. Optimoinnissa tutkittavia yhdisteitä spiikattiin 0-virtsaan niiden ennaltamääritetyn raja-arvon verran, bentsodiatsepiineja 200 ng/ml ja amfetamiinijohdannaisia 300 ng/ml. Bentsodiatsepiinien kohdalla optimoitiin kutakin uuton vaihetta ja optimoinnin tuloksena näytteen pH säädettiin arvoon 5, faasi kunnostettiin asetonitriililla, tasapainotettiin ja pestiin veden (pH 5) ja asetonitriilin (10 % v/v) seoksella ja eluoitiin asetonitriilin, muurahaishapon ja veden (95:1:4 v/v/v) seoksella. Amfetamiinijohdannaisten uutossa optimoitiin näytteen ja liuottimien pH-arvoja ja tuloksena näytteen pH säädettiin arvoon 10, faasi kunnostettiin veden ja ammoniumvetykarbonaatin(pH 10, 1:1 v/v) seoksella, tasapainotettiin ja pestiin asetonitriilin ja veden (1:5 v/v) seoksella ja eluoitiin metanolilla. Optimoituja uuttoja testattiin Yhtyneet Medix Laboratorioista toimitetuilla autenttisilla virtsanäytteillä ja saatuja tuloksia verrattiin kvantitatiivisen GC/MS-analyysin tuloksiin. Bentsodiatsepiininäytteet hydrolysoitiin ennen uuttoa herkkyyden parantamiseksi. Autenttiset näytteet analysoitiin Q-TOF-laitteella Viikissä. Lisäksi hydrolysoidut bentsodiatsepiininäytteet mitattiin Yhtyneet Medix Laboratorioiden TOF-laitteella. Kehitetty menetelmä vaatii tulosten perusteella lisää optimointia toimiakseen. Ongelmana oli etenkin toistoissa ilmennyt tulosten hajonta. Manuaalista näytteensyöttöä tulisi kehittää toistettavammaksi. Autenttisten bentsodiatsepiininäytteiden analyysissa ongelmana olivat virheelliset negatiiviset tulokset ja amfetamiinijohdannaisten analyysissa virheelliset positiiviset tulokset. Virheellisiä negatiivisia tuloksia selittää menetelmän herkkyyden puute ja virheellisiä positiivisia tuloksia mittalaitteen, sirujen tai liuottimien likaantuminen.