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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An Investigation of the Communal Breeding System of the Smooth-billed Ani (Crotophaga ani).

Blanchard, Leanne 09 1900 (has links)
In social systems, the distribution of reproduction among group members is termed reproductive skew. This study was intended to address the issues of reproductive skew within the communally breeding smooth-billed ani employing genetic data to complement behavioural data. The aims of the study were: 1) to develop smooth-billed ani specific DNA markers to be used in the assessment of parentage 2) to determine parentage of buried eggs and surviving offspring to assess whether a reproductive skew pattern is seen 3) to comment on adult relatedness within smooth-billed ani groups. Smooth-billed ani microsatellite DNA sequences were isolated and characterized for use in a parentage/kinship analysis. Lambda Zap Express was used to construct a library of recombinant phage which was screened with TG and AAT probes. Five loci were characterized with between 4 and 9 alleles with heterozygosity values ranging from 0.538 to 0.840. The combined total exclusionary power of the five loci was 0.8869. Offspring loss due to egg destruction in the form of burial has been observed in smooth-billed anis. The issue of reproductive skew as a result of egg burial was addressed by estimating parentage of offspring both buried and remaining in the incubated clutch using 5 species specific microsatellite DNA markers. Evidence for an egalitarian system exhibiting very low skew was found. The significant factors affecting the potential for bias were laying order, laying timing and the number of breeding females. The relatedness of members within a social group may affect the amount of reproductive skew observed. Adults within nesting groups were tested for evidence of relatedness using the pedigree analysis program KINSHIP. Ten percent of dyads showed significant relationships. Low incidence of relatedness provided evidence that smooth-billed ani groups do not contain a large number ofyoung remaining at the natal nest nor was there evidence that regular dispersing within sibling units occurs. There was some evidence that a young male remained on his natal territory while a young female dispersed to a neighbouring territory. Low relatedness between adults and very low reproductive skew were consistent with the prediction of an egalitarian system / Thesis / Master of Science (MS)
2

An Investigation of Territory Quality in the Smooth-Billed Ani (Crotophaga ani) / Territory Quality in the Smooth-Billed Ani

Lentz, Cindy 09 1900 (has links)
Territorial behaviour is exhibited in cooperative breeders. The quality of defended territories can vary, and high-quality sites, which enhance fitness, should be used preferentially over poorer-quality sites. This study was intended to address issues of territory quality within the plural breeding, joint-nesting, smooth-billed ani (Crotophaga ani). I tested the communal joint-nesting threshold hypothesis, which posits that independent pairs will pay the price of group living if compensated by acquiring a superior territory. My results quantified differences in territory quality in terms of time of first breeding and chances for re-nesting or second-brooding. Per capita territory quality correlated negatively with group size, in conflict with the communal joint-nesting threshold hypothesis. Another hypothesis to explain communal behaviour is the habitat saturation hypothesis. This postulates that offspring remain in their natal territory and delay reproduction because of a local absence of suitable breeding habitat. I tested the habitat saturation hypothesis, which was developed to explain the evolution of group living in cooperatively breeding birds. I compared occupied ani territories with vacant sites, using eight ecological variables that may be important to the fitness of a group. In addition, I compared occupied territories with sites that were occasionally occupied. I did not find the habitat of our population of smooth-billed anis to be saturated. Some sites were never occupied because there are territory characteristics that presumably limit breeding. In contrast with expectations of habitat saturation, there were suitable sites available for breeding that were not in use. Results from both hypotheses presented suggest that there are not obvious group-living benefits and that one must consider other explanations for the evolution and maintenance of this system. / Thesis / Master of Science (MS)
3

Identifizierung von Genomregionen, die für Analatresien des Schweines prädestinieren

Wiedemann, Sabine Elisabeth. Unknown Date (has links)
Techn. Universiẗat, Diss., 2004--München.
4

Microsatellite DNA Analysis of the Communal Breeding System of the Smooth-billed Ani (Crotophaga ani) in Southwest Puerto Rico

Startek, Jennifer Melissa 05 1900 (has links)
The communal breeding system of the smooth-billed ani (Crotophaga ani) was studied at two wildlife refuges in southwest Puerto Rico. Groups ranged in size from 2 to 9 adults, and communal clutches ranged in size from 11 to more than 25 eggs. Microsatellite DNA loci were isolated and used to examine the mating system and the extent of reproductive skew in individual groups. Loci were also screened in guira cuckoos (Guira guira) to examine the relationships suggested by Quinn et al. (1994). In the four focal smooth-billed ani groups, I found suggestions of monogamy, polygamy, and incidents of intraspecific brood parasitism. In all groups, incubated clutch size and microsatellite data indicate that subordinate females are gaining some reproductive success. At one nest, evidence suggested a decrease in the intensity of reproductive skew between successive nests. Although the data are limited, they suggest that alternative strategies to monogamy may be more prevalent than previously believed, and that reproductive skew may be affected by the availability of limiting resources within the breeding season. / Thesis / Master of Science (MS)
5

Nestling Provisioning in a Joint Nesting Cuckoo: The Smooth-Billed Ani (Crotophaga Ani)

Samuelsen, Annika 09 1900 (has links)
Abstract Not Provided / Thesis / Master of Science (MSc)
6

Sexual Dimorphism in a Joint-Nesting Plural Breeder, the Smooth-Billed Ani (Crotophaga ani) / Sexual Dimorphism in Smooth-Billed Anis / Sexual Selection in a Joint-Nesting Plural Breeder, the Smooth-Billed Ani (Crotophaga ani)

Barclay, Megan 09 1900 (has links)
Sexual selection has been investigated in many different systems but information is lacking in joint-nesting species. Both sexual dimorphism and possible signals of quality were explored in this study for a joint-nesting plural breeder, the smooth-billed ani (Crotophaga ani). Sexual dimorphism can be examined for a species in an attempt to reveal particular traits that might be under sexual selection and the strength of sexual selection on them. In mate choice decisions, sexually selected traits may be used by the choosy individual to assess the quality of potential mates. These honest traits need to reveal the condition and genetic quality of the individual accurately. For example, it has been proposed that plumage colour reveals condition, and more specifically parasite resistance in birds. This study explores sexual size dimorphism and dichromatism in smooth-billed anis, as well as the ability of their feather colour to reveal body condition (measured as residuals from a regression of mass versus body size), body size, and parasite numbers. Additionally, because anis are group living birds, this study investigated whether group size had an effect on parasite numbers. Anis from a population in southwestern Puerto Rico were measured for size, their feathers were collected and analyzed using a spectrometer, and ectoparasites were collected by dustruffling. For all size traits measured, males were significantly larger than females. Males also had more exaggerated bill depths (relative to body size) than females. There were no differences between the sexes for all colour morphometries, except tail saturation; females had more saturated tails than males. While no decisive conclusions can be drawn as to why the dimorphic traits are different between males and females, sexual selection may have played a role. The relationship between log10 average lice numbers per group and group size was positive, but not significant. In male smooth-billed anis, plumage colour was not related to lice or mite numbers, or body size and body condition. Plumage colour was also not related to body condition and size in females. Additionally, ectoparasites did not have an effect on male body condition. Plumage may not only be an inaccurate signal of parasite resistance or body size and body condition in the smooth-billed ani, but ectoparasites may not even have a negative effect on their host. The inability to find significant results may have been affected by other factors, such as feather wear and the age of individuals. These results warrant a more detailed look into the social behaviour of the group-living smooth-billed ani. / Thesis / Master of Science (MSc)
7

Biomechanické následky tržných poranění musculus levator ani vzniklých při vaginálním porodu / The biomechanical effects of levator ani muscle laceration injuries after vaginal delivery

Křepelka, Petr January 2013 (has links)
Title: The biomechanical effects of levator ani muscle laceration injuries after vaginal delivery Objectives: The aim of this thesis is to sum up current knowledge about the normal structure and function of levator ani muscle and findings about dysfunctions of a pelvic floor. By means of biomechanical instruments to analyse how the lower part of levator ani muscle closes (puborectalis muscle) during unilateral avulsion lesion. On the basis of computer simulation of biomechanical properties of the pelvic floor during avulsion lesion to describe the theoretical solutions for the therapy of the main types of dysfunctions of the pelvic floor. Methods: Biomechanical analysis was used with a help of computer model of muscular pelvic floor with a help of the ABAQUS model. This model with matched properties of muscular tissue was influenced by the standard pressure which influences the pelvic floor for a person of 80 kilos standing at rest. This model simulated unilateral avulsion lesion and biomechanical variables were observed during compensatory activation of uninjured parts of levator with the activity 100%, 50% and 10%. The map of the muscular tone and the rate of movement of the muscles of the pelvic floor were evaluated. Results: Only minimal movement is observed in the intact pelvic floor during...
8

Anisotropic Muscle Phantoms for Shear Wave Elastography Assessment of the Levator Ani Muscle Properties / Anisotropiska muskelfantomer för utvärdering av levator ani-muskeln med skjuvvågselastografi

Koxha, Bleona, Jova Martinez, Melissa January 2023 (has links)
Pelvic floor disorder is an emerging research area and is highlighted in many pelvic floor studies. Assessment methods for this type of injury are lacking and new methods for prevention and diagnosis are needed. Pelvic floor disorders are common among women and can lead to suffering for the patient. Levator ani muscle injuries are the main cause for pelvic floor disorders. This muscle group is an anisotropic skeletal muscle that helps support the pelvic viscera. Assessment of this muscle is difficult due to its complex geometry and location. Therefore, two muscle phantoms were constructed to mimic different properties of the levator ani muscle. The muscle phantoms provided more availability and a more controlled setting. The muscle phantoms were examined using ultrasound-based shear wave elastography which is an elastography method that can help determine the elasticity of tissue. A PVA-graphite phantom and a water-based gelatine-graphite phantom, both with fishing lines network as fibers for anisotropy, were constructed in this project. Shear wave elastography results of the PVA phantom indicated no anisotropy but visually resembled a muscle. Although not achieving anisotropy, the shear modulus of the PVA did match the shear modulus of skeletal muscle tissue. Shear wave elastography results of the gelatine phantom indicated anisotropy but visually did not resemble a muscle due to the low shear modulus of the gelatine. A 3D model of the female bony pelvis, that was provided for this project, was measured, and compared with reference value of previous study for future construction and 3D printing of the model. Results of measurements showed similarities between the 3D model and the female pelvis except for the sagittal outlet which had a deviant value. For future work, the muscle phantom can be developed by applying the complex geometry of the levator ani muscle, assembly of the muscle phantom, and the 3D rendering of the pelvis. The combination of these two parts provides a more complete phantom where shear wave elastography can be applied in the same way as in female patients. / Bäckenbottenbesvär är ett framväxande forskningsområde och lyfts fram i många bäckenbottenstudier. Bedömningsmetoder för denna typ av skador saknas och det behövs nya metoder för förebyggande och diagnostik. Bäckenbottenbesvär är vanliga bland kvinnor och kan leda till lidande för patienten. Levator ani muskelskador är den främsta orsaken till bäckenbottensjukdomar. Denna muskelgrupp är en anisotrop skelettmuskel som hjälper till att stödja inälvorna i bäckenet. Bedömning av denna muskel är svår på grund av dess komplexa geometri och läge. Därför konstruerades två muskelfantomer för att efterlikna olika egenskaper hos levator ani-muskeln. Muskelfantomerna gav mer tillgänglighet och en mer kontrollerad inställning. Muskelfantomerna undersöktes med hjälp av ultraljudsbaserad skjuvvågselastografi som är en metod som kan hjälpa till att bestämma vävnadens elasticitet. En PVA-grafitfantom och en vattenbaserad gelatin-grafitfantom, båda med fiskelinsnätverk som fibrer för anisotropi, konstruerades i detta projekt. Resultat från skjuvvågselastografi på PVA-fantomen indikerade ingen anisotropi, men liknade visuellt en muskel. Även då anisotropi inte uppnåddes, så matchade skjuvmodulen för PVA skjuvmodulen för skelettmuskelvävnad. Resultat från skjuvvågselastografi på gelatinfantomen indikerade anisotropi dock visade resultatet ingen visuell liknelse av en skelettmuskel på grund av gelatinets låga skjuvmodul. En 3D modell av bäckenbenet, som förseddes det här projektet, mättes och jämfördes med referensvärde av tidigare studie för framtid 3D friformsframställning av modellen. Resultat av mätningar visade på liknelser mellan 3D modellen och det kvinnliga bäckenbenet förutom sagittal outlet som hade ett avvikande värde. Inför fortsättning av det här projektet kan en utveckling av muskel fantomen ske genom applicering av den komplexa geometrin hos levator ani muskeln samt sammansättning av muskel fantomen och 3D framställningen av bäckenbenet. Sammansättningen av dessa två delar ger en mer komplett fantom där skjuvvågselastografi kan appliceras på samma sätt som hos kvinnliga patienter. / Ja
9

The Murji'a and the theological school of Abū Ḥanīfa : a historical and ideological study

Givony, Joseph January 1977 (has links)
Towards the end of the 7th century A.D., Iraq was in a state of near civil war, caused by social and political malaise. Factional and tribal feuds and fierce antagonism to the Umayyad reign threatened the survival of the dynasty as the unifying force of the empire. Into this situation, al-Ḥasan b. Muḥammad b. al-Ḥanafiyya (d.c. 100/718), a grandson of 'Alī, introduced a peace formula which was intended to pacify the rival religio-political parties. This idea found adherence especially among religious scholars, who quickly broadened its basis, attracting followers to its pacific message. Despite an unstable record of relations with the court, the movement basically supported with its ideology the legitimacy of the Umayyad reign. The popularity of the movement, especially in some scholarly circles in Kufa, led to the formation of a school of religious thought, which had relied on the basic political and religious attitudes of the early Murji'a, but transformed it into a comprehensive theological system. Although not responsible for the actual forging of Murji'ite attitudes, Abū Ḥanīfa had emerged as the eponymous epitome of the movement and the theological school. The first chapter, "Irjā', The Development of the Idea", investigates several possibilities as the source of this notion, among them the alleged Qur'ānic origin, and the Kitāb al-Irjā' attributed to al-Ḥasan b. Muḥammad b. al-Ḥanafiyya. The second chapter, "The Formation of the Murji'a as a ReligioPolitical Movement" surveys the social and the historical background of the Kufan milieu, the formation of the Murji'ite circle and the social elements it was comprised of, and the position of the movement in political and religious affairs in the first two decades of the 8th century .A.D. The third and last chapter, "The Transformation of the Murji'a from a Political into a Religiously-Oriented School" studies and analyses what is believed to be genuine Murji'ite treatises of religious thought, in comparison to sources of a contemporary rival school and the heresiographers. Special emphasis was laid in the analysis on the subject of theology as a medium for political views.
10

Surface Electromyography of the Pelvic Floor Musculature: Reliability and Validity of a Novel Electrode Design

Keshwani, Nadia 07 February 2011 (has links)
Purpose: Intravaginal probes used for recording electromyography (EMG) from the pelvic floor muscles (PFMs) likely record activity from nearby muscles (crosstalk), and move during functional tasks, causing motion artifact data contamination, threatening the validity of results obtained. This study investigated the test-retest reliability and validity of surface EMG recordings from the PFMs using a novel, theoretically superior electrode in comparison to a commercially available intravaginal probe, the FemiscanTM. Methods: Healthy subjects (n=20) performed tasks with each vaginal electrode in situ: i) PFM maximal voluntary contractions (MVC), ii) coughs, iii) unilateral hip adductor/external rotator contractions at 25%MVC, 50%MVC, and MVC while keeping the PFMs relaxed or maximally contracted, and iv) transversus abdominis contractions (TrA; recorded using fine-wires) at 25%MVC, 50%MVC, MVC. Analyses: i) Intraclass correlation coefficients (ICC), ii) t-tests of proportions (α=0.05), iii) repeated measures ANOVAs and Tukey’s post-hoc testing (α=0.05) and iv) cross-correlation functions between peaks of transversus abdominis and PFM activity were used to determine the between-trial and between-day reliability of each vaginal electrode, a difference in prevalence of motion artifact contamination between electrodes, and the presence of crosstalk from the hip and TrA, respectively. Results: Between-trial reliability of both vaginal electrodes was excellent (ICC(3,1)=0.943-0.974). Between-day reliability was less consistent (ICC(3,1)=0.788-0.924 and 0.648-0.715 for the FemiscanTM and novel electrode, respectively). No significant difference in the proportion of files contaminated with motion artifact using each electrode existed. At submaximal intensities of hip muscle contractions, the FemiscanTM recorded significantly higher EMG amplitudes compared to what it recorded when the hip was relaxed, whereas the novel electrode did not, indicating that the FemiscanTM recorded crosstalk from the hip musculature. Low cross-correlation coefficients (<0.90) and large time delays (≥ 0.5 milliseconds) between peaks of PFM and TrA activity indicated that neither vaginal electrode recorded crosstalk from the TrA. Conclusion: The novel electrode is a promising tool to record EMG from the PFMs, as it records less crosstalk from the hip musculature than current technology while maintaining a high degree of reliability when comparing results collected within the same session; however, this electrode should not be used to compare one’s muscle activity between days. / Thesis (Master, Rehabilitation Science) -- Queen's University, 2011-02-07 14:46:30.811

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