Browsing by Subject "morphology"

This project is a corpus-based study on numeral + noun phrases in Scottish Gaelic. The typical pattern in Scottish Gaelic is to use a singular noun after numerals one and two and a plural noun after numerals three through ten. However, there are some nouns that do not follow this expected pattern. These exceptions are called numeratives and there are three different categories of numeratives in Scottish Gaelic: duals, numeratives identical in form to a singular, and numeratives with a form that differs from singular and plural and only used with numerals. This study aims to find which nouns have numerative forms and how their use varies diachronically and between dialects. While numeratives have been more researched in Welsh and Irish, there is not much research on numeratives in Scottish Gaelic. Ò Maolalaigh (2013) did a more restricted corpus study to find what nouns use singular after numerals three through ten. The past research provides a good comparison for my results and gives me a good foundation to expand on. From the past research, there seems to be a semantic relationship between the kinds of nouns that have numerative forms, so I sort my results into semantic categories as well. I also look at numeratives from the perspective of linguistic complexity since Scottish Gaelic is a minority language with a large proportion of L2 speakers. This project uses Corpas na Gàidhlig (the Corpus of Scottish Gaelic), which is part of the University of Glasgow’s Digital Archive of Scottish Gaelic. I search the corpus for numerals two through four to see which nouns use numeratives and how consistently they use them. I also look at how frequently numeratives are used diachronically and how usage varies across dialects. I focus especially on nouns that have a high number of numerative tokens to see if there is a pattern in their usage. In my results, I found 47 nouns that use a dual form and 105 nouns that use a numerative identical in form to a singular. The overall findings for numerative use are that dual use is decreasing, while use of numeratives identical in form to singular has been increasing since 1900-1949. The semantic category with the most dual tokens is natural pairs. The nouns with numeratives identical in form to singular tend to be nouns frequently used with numerals, such as measurement words.

In recent years, exceptionally large bacteriophages with genome sizes over 500 kilobase pairs (kbp), called megaphages, have been discovered from sequence data, but no previous publications discussing megaphage isolates have been published. In 2011, a phage infecting a Flavobacterium strain was isolated from the Kymijoki river. The phage, named FKy-1, was determined to have a genome size of 643 kbp, based on yet unpublished results, making it the first described megaphage isolate. In this study, we focused on characterizing megaphage FKy-1, by observing the virus morphology, determining the type and length of its life cycle, and measuring its stability in different temperatures and conditions. Purification of the phage by precipitation and ultracentrifugation in a sucrose density gradient resulted in separation of both virion and phage subcomplexes. Based on transmission electron microscopy and cryogenic electron microscopy, FKy-1 was observed to have typical myovirus morphology, with a large icosahedral head of around 160 nm in diameter, and a tail of around 180 nm in length. Molecular masses of the major proteins present in the virion and phage subcomplexes were estimated using sodium dodecyl sulfate polyacrylamide gel electrophoresis to be 50-70 kDa for the major capsid protein, 60-70 kDa and 150-200 kDa for the major tail proteins. Digestion attempts with restriction endonucleases proved unsuccessful, indicating possible phage genome modifications or other defensive mechanisms. The phage was determined to have a lytic life cycle which takes over 3 h to cause cell lysis, resulting in the release of around 10 progenies per infected host cell. The phage proved to be quite stable, with minimal impact on infectivity measured at a temperature range of -20 °C to +40 °C, and in minimal buffer conditions. In summary, we proved that the purification method used here is well suited for megaphages, and that FKy-1 is of myovirus morphology, produces a low number of progenies per host, and is relatively stable. As no other publications regarding megaphages exist, this study acts as a good basis for future research regarding megaphage morphology, infection cycle and stability.

Morphological features are considered as markers of microglial functionality, and they show regional heterogeneity in the brain. Recently the sleep-wake cycle was shown to affect microglial morphology in mice and correlate with cortical sleep slow wave activity (SWA). Microglial sizes and ramification increased during the dark period and decreased during the light period in cerebral areas associated with SWA, suggesting that neuronal activation could be affecting microglial morphology through SWA. I studied microglia in the hindbrain areas with and without functional connection to SWA to further investigate the association between SWA and alterations in morphology, and to investigate if there are differences in microglial morphology and their diurnal alterations in brain regions other than those commonly investigated. I examined three hindbrain areas (cerebellar cortex (CC), deep cerebellar nucleus (DCN) and medial vestibular nucleus (MVN)) and somatosensory cortex (SC) of mice (n=15) at two timepoints: 6 hours after the light onset (high SWA) and offset (low SWA). My aims were to answer if there are morphological differences in microglia between 1) the four brain areas at both timepoints and 2) between the two timepoints in each brain area. My hypotheses were that CC and DCN which have functional connections to cortical SWA, would show similar diurnal morphology alterations as demonstrated in the cerebral areas, and MVN that has no known cortical SWA connection, would lack significant alterations. As microglia are heterogenous throughout brain, I expected microglia to differ between different brain areas, especially the hindbrain and the SC. I found that microglial morphologies significantly differed between the hindbrain and the cortex, while the hindbrain areas were more similar in morphology. Moreover, the brain areas demonstrated diurnal morphology alterations of microglia with varying extent: CC and DCN microglial morphology did not correlate with SWA as clearly as SC did, and interestingly, morphological features of MVN microglia showed a pattern opposite to other areas, microglia being larger during the light period than the dark period. These results highlight the importance of the diurnal time to microglial morphology and the heterogeneity of microglia between different brain regions.

Wooden breast is muscle myopathy occurring in broilers, myopathy forms hard and pale connective tissue areas in broiler breast muscles. When wooden breast is occurring also some other myopathies can coexist: loose muscle structure and white stripping are visible on breast muscles. The myopathy is relatively new and it was noticed approximately ten years ago in greater amounts. The subject of this thesis was to study wing flapping and how it affects the morphology of breast muscles and bones and whether there are links between them and wooden breast prevalence. The literature review handled muscle morphology and bones morphology and how muscles shape changes when they grow in size, how muscles and bones grow normally and how the exercise of the muscles will affect wooden breast prevalence. In the literature review the anatomy of broiler movement and especially the anatomy of bones and the muscles that are involved in wing movement is handled. The study is made by raising 171 broiler birds divided in three groups: Group A birds have feed and water on floor level and birds do not have to use their wings. Group B birds lived same way as A-group until at day 25 drinking water is moved to platform which is higher than the floor level. Birds had to fly to platform and down when they need water or feed. Group C feed and water were on floor level but after 3 days water was risen on the platform and platform was risen gradually when birds grew and all birds of the Group C learned how to get to platform. From the original 171 birds 17 were sacrificed outside the study due health reasons. The birds (171-17 i.e. 154) were terminated 20, 30 or 41 days old in 40, 58 or 56 bird batches. The percentage of termination was roughly equal in each group on each termination, except at Day 20, when Group A and Group B had had the same treatment, and there were no terminations in Group B. The aim of this thesis was to study effects of wing flapping to broilers morphological changes. This thesis showed that there were no significant differences in Group A and Group C between studied properties. Wing flapping showed no significant differences during sample termination days in morphological properties.

Objective: Recent research has shown that simple novel words can be acquired rapidly through a short repetitive exposure without focused attention. However, monomorphemic words construct only a part of a language – little research has focused on the rapid acquisition of novel suffixes attached to familiar word stems. The present study was conducted to explore the online acquisition of novel suffixes by investigating how the measured neural activity in response to the newly learned suffix changes over a passive listening session; and to examine if a short consolidation period, containing either sleep or wakefulness, affects this change. Methods: Participants were trained with novel suffixes using a semantic word-picture association task. Afterwards, their neural activity was monitored with electroencephalography (EEG) during two passive listening phases for 15 min in total, and the event-related potentials to different types of suffixes (real, semantically trained novel, or untrained novel) attached to real word stems were measured. In addition, the experiment contained a 90-min retention period of either sleep or wakefulness between the passive listening phases. To identify changes in neural activity, linear regression models from different conditions were compared against their respective null models using a chi-squared goodness-of-fit test. To examine the effects of different conditions on the degrees of change of neural activity, a repeated measures analysis of variance was conducted. Results and conclusion: In line with previous rapid learning research, the results indicate that neural activation in response to novel suffixes can increase without overnight consolidation. A relatively short offline retention period can increase the degree of change of neural activation in response to novel suffixes, although no conclusive sleep-related effects were found.

Kierresiipiset (Insecta: Strepsiptera) ovat toisten hyönteisten loisia, joille on tyypillistä monimutkaiset elinkierrot sekä sukupuolten äärimmäinen erilaisuus. Kierresiipisten elinkiertoon kuuluu kolme sisäloistoukkavaihetta. Suurimmalla osalla kierresiipisistä ensimmäinen toukkavaihe sekä aikuiset koiraat elävät vapaina ja naaraat ovat koko elämänsä sisäloisia. Lentokykyiset koiraat muistuttavat hieman kärpäsiä, kun taas naaraat ovat toukkamaisia. Kierresiipisiä tunnetaan noin 630 lajia. Lajien ulkoisen samankaltaisuuden vuoksi lajimäärä on todennäköisesti paljon suurempi. Andrena-suvun maamehiläisissä loisiva Stylops-suku on yksi suurimmista kierresiipissuvuista. Aiemmin Euroopassa on ajateltu esiintyvän vain yksi suvun laji, Stylops melittae, mutta DNA-menetelmiä hyödyntävä tutkimus osoitti sen olevan 30 lajin lajikompleksi. Tässä tutkimuksessa selvitin, mitkä näistä lajeista esiintyvät Suomessa. Lisäksi tarkastelin voiko meillä esiintyvien naaraiden morfologiaa hyödyntää lajinmäärityksessä, sillä koiraita tavataan äärimmäisen harvoin. Tutkimustani varten kävin läpi Suomen suurimpien hyönteiskokoelmien kaikki Andrena- isäntälajiyksilöt ja tallensin havaittujen kierresiipisten löytötiedot tietokantaan. Tein soveltuville yksilöille DNA-viivakoodianalyysin ja vertasin saatuja DNA-viivakoodeja tietokantojen viivakoodeihin. Morfologisessa tarkastelussa irrotin Stylops-naaraat isännistä ja tarkastelin eri kuvantamismenetelmin otetuista kuvista (kerrosvalokuvaus, SEM) naaraiden rakenteiden mittoja sekä ulkonäköä. Tutkimukseni perusteella Suomessa esiintyy aiemmin luullun yhden lajin sijaan viisi Stylops-lajia: S. thwaitesi, S. ater, S. japonicus, S. nevinsoni ja S. spreta. Näiden lisäksi Suomessa esiintyy yksi todennäköisesti kuvaamaton laji. Näiden kaikkien lajien naaraat eroavat toisistaan morfologialtaan. Koostin jokaisesta lajista yhteenvedot, jotka sisältävät tietoa niiden morfologiasta, ekologiasta, levinneisyydestä sekä yleisyydestä. Tutkimukseni antaa arvokasta tietoa Suomen kierresiipislajistosta. Siinä tarkasteltiin ensimmäistä kertaa Stylops-suvun esiintymistä nykyisen taksonomisen luokittelun mukaisesti Suomessa. Tutkimukseni antoi lisätietoa Stylops-lajien esiintymisalueista. Stylops japonicus esiintyy aiemmista tiedoista poiketen myös Euroopassa. Lisäksi se antoi uutta tietoa usean lajin isäntälajisuhteista. Monia aineistoni Andrena-isäntälajeja ei olla yhdistetty aiemmin tiettyihin kierresiipislajeihin. Kierresiipisiin keskittynyttä tutkimusta ei ole ollut pitkään aikaan Suomessa. Tutkimusta varten keräämääni aineisto toimii hyvänä pohjana tulevaisuuden tutkimuksille. Tuloksia hyödynnettiin Suomen uhanalaisten eliöiden arvioinnissa 2019, jonka mukaan kaksi Stylops-lajeista ovat uhanalaisten lajien punaisella listalla.

Lepidurus arcticus (Pallas, 1793) is a keystone species in High Arctic ponds, which are exposed to a wide range of environmental stressors. This thesis provides information on the ecology of this little studied species by paying particular focus on the sensitivity of L. arcticus to acidification and climate change. Respiration, reproduction, olfaction, morphology, salinity and pH tolerance of the species were studied in the laboratory and several environmental parameters were measured in its natural habitats in Arctic ponds. Current global circulation models predict 2–2.4 °C increase in summer temperatures on Spitsbergen, Svalbard, Norway. The L. arcticus respiration activity was tested at different temperatures (3.5, 10, 16.5, 20, 25 and 30 °C). The results show that L. arcticus is clearly adapted to live in cold water and have a temperature optimum at +10 °C. This species should be considered as stenothermal, because it seems to be able to live only within a narrow temperature range. L. arcticus populations seem to have the capacity to respond to the ongoing climate change on Spitsbergen. Changes can be seen in the species' reproductive capacity and in the individuals' body size when comparing results with previous studies on Spitsbergen and in other Arctic areas. Effective reproduction capacity was a unique feature of the L. arcticus populations on Spitsbergen. L. arcticus females reached sexual maturity at a smaller body size and sexual dimorphism appeared in smaller animals on Spitsbergen than anywhere else in the subarctic or Arctic regions. L. arcticus females were able to carry more eggs (up to 12 eggs per female) than has been observed in previous studies. Another interesting feature of L. arcticus on Spitsbergen was their potential to grow large, up to 39.4 mm in total length. Also cannibalistic behaviour seemed to be common on Spitsbergen L. arcticus populations. The existence of different colour morphs and the population-level differences in morphology of L. arcticus were unknown, but fascinating characteristic of this species. Spitsbergen populations consisted of two major (i.e. monochrome and marbled) and several combined colour morphs. Third interesting finding was a new disease for science which activated when the water temperature rose. I named this disease to Red Carapace Disease (RCD). This High Arctic crustacean lives in ponds between the Arctic Ocean and glaciers, where the marine environment has a strong impact on the terrestrial and freshwater ecosystems. The tolerance of L. arcticius to increased water salinity was determined by a LC50 -test. No mortality occurred during the 23 day exposure at low 1–2 ‰ water salinity. A slight increase in water salinity (to 1 ‰) speeded up the L. arcticus shell replacement. The observations from natural populations supported the hypothesis that the size of the animals increases considerably in low 1.5 ‰ salt concentrations. Thus, a small increase in water salinity seems to have a positive impact on the growth of this short-lived species. Acidification has been a big problem for many crustaceans, invertebrates and fishes for several decades. L. arcricus does not make an exception. Strong acid stress in pH 4 caused a high mortality of mature L. arcticus females. The critical lower limit of pH was 6.1 for the survival of this acid sensitive species. Thus, L. arcticus populations are probably in danger of extinction due to acidification of three ponds on Spitsbergen. A slight drop (0.1–1.0) in pH values can wipe out these L. arcticus populations. The survival of L. arcticus was strongly related to: (1) the water pH, (2) total organic carbon (TOC) and pH interaction, (3) the water temperature and (4) the water salinity. Water pH and TOC values should be monitored in these ponds and the input of acidifying substances in ponds should be prevented.