Lotus corniculatus L. (Legtuninosae), is a perennial herb common throughout Britain. Its main pollinators are bumblebees (Bombus spp., Apidae: Hymenoptera). This is a study of the ecological factors which are important to flowering and fruiting in the species, and some of their evolutionary implications. The work was carried out at Wytham Estate, Oxfordshire, U.K., mainly in an ex-arable field (Upper Seeds) and a more established grassland (Lower Seeds Reserve). The literature on self-incompatibility in L. corniculatus is reviewed; there are conflicting reports, but wild material is fundamentally self-incompatible. Plants in Upper Seeds are larger than in Lower Seeds Reserve. Comparative data on soil nutrients in the two sites suggests that the cause is the persistence of phosphorus from inorganic fertiliser. There is a positive, linear relationship between plant size, flower production and fruit production. The species regulates investment in flowers mainly at the level of the whole inflorescence, rather than altering number of flowers per inflorescence. Within individuals, there are no consistent trade-offs between number of fruit per infructescence, numbers of seeds per fruit and seed weight. Weather patterns only partially explain the flowering phenology of L. corniculatus. Timing of first flowering and peak flowering are correlated but are variable between individuals, and between years for the same individuals. They are not correlated with flowering synchrony. An individual's flowering pattern does not consistently affect fruit-set; the overriding determinant of fruit production is plant size. Selection is therefore unlikely to be acting on flowering time in this species. The production of large numbers of self-incompatible flowers does not seem to reduce fruit-set; pollinators do not visit enough flowers per foraging trip (perhaps because nectar production is low) for geitonogamy to become a problem. Seed predation by larvae of a chalcid wasp, a weevil and a moth differs between individual plants, but not consistently so between years. Seed predation is not consistently correlated with plant size, mean flowers per inflorescence, number of seeds per fruit or seed size. There is no evidence for selection acting on these traits through seed predation. Partially predated seeds are often viable, which may have implications for seedling demography. Seed predation and flowering phenology are not defmitively linked, strengthening the argument that flowering time is not adaptive in this species.

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Thesis (M.S.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-01

Nous avons mis au point un nouveau protocole expérimental multi-générationnel permettant d’étudier la plasticité du copépode Eurytemora affinis dans le cadre d’un scénario de changement climatique. Cette espèce cryptique a été capable de se développer à des fortes températures et/ou salinités en montrant des effets de contrôle maternel et trans-générationnels sur ses traits de cycle de vie. Compte tenu de l’importance de la reproduction, nous avons étudié la stratégie reproductive des femelles, des mâles et de leur interaction. Nous avons mis en évidence, la présence de trade-off entre la fécondité et la taille de l’œuf chez le copépode. Nous avons également montré une nette différence entre les populations transatlantiques d’E. affinis. L’analyse détaillée des rôles du mâle et de la femelle dans la reproduction des copépodes a été illustrée pour la population d’E. affinis provenant de la Seine. Nos résultats ont révélé que ; le mâle contribue activement à la reproduction puisqu’il est capable d’identifier les femelles prêtes à s’accoupler, la femelle est capable de s’accoupler avec plusieurs mâles et d’utiliser pour une même portée le matériel génétique de plusieurs pères. Il semble qu’un sex-ratio en faveur des males offre des avantages avérés à la population d’E. affinis de l’estuaire de la Seine. Les résultats de cette thèse confirment le grand potentiel de ce copépode comme modèle biologique et soulignent l’importance d’intégrer la plasticité des organismes vivants et leur capacité d’adaptation aux variations de la température ainsi que d’autres facteurs environnementaux dans le cadre des effets du changement climatique sur les écosystèmes. / We developed a new multigenerational experimental protocol allowing to study the plasticity of the copepod Eurytemora affinis within the framework of a climate change scenario. This cryptic species was capable to develop under high temperatures and/or salinities, showing trans-generational and maternal control effects on its life cycle traits. By considering the importance of the reproduction, we studied the reproductive strategy of females, males and their interaction. We underlined the presence of trade-off between the fecundity and the offspring size in copepods. We also showed a clear difference between the transatlantic populations of E. affinis.The detailed analysis of the respective roles of the male and the female in the reproduction of copepods was illustrated for the population of E. affinis from the Seine. Our results revealed that; the male contributed actively to the reproduction being able to identify females ready to mate; the female was capable of multiple mating and of using the genetic material of several fathers for the same clutch. It seems that a sex-ratio in favor of males offered clear advantages to the population of E. affinis from the Seine estuary.The results of this thesis confirmed the high potential of this copepod as biological model and underlined the importance of integrating the plasticity of the living organisms and their capacity of adaptation to temperature variations or any other environmental factors within the framework of the effects of climate change on the ecosystems.

Thesis (MPH) -- University of Limpopo, 2012. / Background: Youth friendly services were introduced in all the ten districts t of Lesotho to meet the adolescents health needs including reproductive health of adolescents. Despite this initiative there is still a high prevalence of teenage pregnancy and human immunodeficiency virus (HIV) infection among young people. Aim: The aim of the study was to investigate the utilization, and factors influencing the utilization of reproductive health services (RHS) among high school adolescents in Thaba-Tseka district of Lesotho. Methodology: This was a quantitative descriptive cross-sectional study. The study population was adolescents aged between 13 -19 years in the two high schools in the district. A total of 800 adolescents were asked to complete a structured, self-administered questionnaire. Descriptive statistics were used to summarise demographics, sexual activity, experience of sexually transmitted infections (STIs), and awareness and use of RHS. The chi-square test was used to identify associations between categorical variables, and binary logistical regression modelling was used to identify significant predictors of utilisation of RHS. Results: The response rate was 97.5% (780/800), but only 723 questionnaires had sufficient data to be analysed. The mean age of respondents was 16.4 years with a standard deviation of 1.7years. Of the respondents, 49.5% (358/723) had been sexually active with the youngest age at sexual debut of 8 years. Of these, 71.5% (256/358) were presently sexually active; 82.4% (295/358) had low overall levels of awareness of RHS; 37.9% (136/358) had ever visited the adolescent health corner (AHC); 34.9% (125/358) reported that there was a place that provided RHS in their local clinic; 57.3% (205/358) had ever used condoms; and 56.7% (203/358) had experienced a STI; Of those presently sexually active, 89.5% (229/256) used some form of contraceptive, with 95.2% (218/229) buying condoms from a retail shop although only 94.0% (205/218) reported using them, while 38.9% (89/229) also obtained them from the AHC. Only 13.3% (27/203) of those who had experienced signs of STI ever visited the AHC for treatment. Of those who knew about RHS, 54.4% (68/125) utilized the services. Statistically significant predictors of RHS utilization were having a friend using RHS (odds ratio [OR] =8.87; P value< 0.001) and access to RHS (OR=7.97; P < 0.001). Participants in higher grades were significantly less likely to use RHS compared to participants in lower grades (OR=0.21; P<0.001). Conclusion: Almost half of the adolescents engage in sexual activity at an early age and RHS are under-utilised, mostly because of lack of access. There is a need to embark on increasing accessibility of RHS among adolescents to promote utilization of RHS.

Doctor of Philosophy (PhD) / Reproductive physiology plays a vital role in population growth and vitality. Baseline data on reproductive physiology and a comprehensive knowledge of breeding biology are essential to conservation management. Great whales have been hunted from the 16th century to the present day. Although many populations are increasing there are populations with low or declining reproductive rates. In 2001 it was recommended to the International Whaling Commission that new techniques be developed to assess the internal physiology of great whales. This study, based on this recommendation, aims to develop analytical methods to assess reproductive hormones in cetacean blow samples and determine the feasibility of its use with free-swimming great whales. A method for the assessment of steroid hormone concentrations using liquid chromatography-mass spectrometry (LC-MS) was developed and validated. These methods were then used to determine testosterone and progesterone concentrations in saliva and blow of bottlenose dolphins. The stability of testosterone and progesterone was found to be a major issue. Without inhibitors, hormone concentrations increased by up to 65% over three hours at 21oC. Storing samples at low temperatures (-20oC or -80oC) slowed but did not cease the rate of change. The addition of inhibitors, manganese chloride and amoxycillin potassium/clavulanate, improved the stability of testosterone and progesterone. It is proposed that when using dolphin saliva and blow samples to measure reproductive hormones the samples are extracted as soon as possible after collection to prevent degradation. This study highlighted the need to address steroid hormone stability prior to any longterm biological program, to ensure that changes seen in hormone concentration are due to biological activity rather than storage. A technique to collect blow samples from free-swimming great whales was developed. This technique, in conjunction with the specially developed LC-MS methods allowed for the determination of testosterone and progesterone concentrations in humpback whale blow. The techniques developed in this study to determine reproductive hormones in cetacean saliva and blow have applications for both captive and wild population studies. In captive institutions, saliva and/or blow can be used to monitor reproductive cycling in both females and males. As it is noninvasive it can be used on a daily basis with minimal stress to the animals. The use of blow sampling has the capacity to improve our understanding of reproductive cycling in great whales as it can be used to sample animals in both the breeding and feeding areas. This technique may allow us to now examine whether reproductive dysfunction is playing a role in the slow recovery of critically endangered species such as the North Atlantic right whale.

Syftet med studien var att jämföra effekterna mellan tidig eller uppskjuten oxytocinbehandling vid värksvaghet under förlossning samt att studera hur intaget av peroral vätska och/eller intravenös infusion kunde påverka förlossningsutfallet. Metod en prospektiv randomiserad kontrollerad studie där även jämförelse med kontrollgrupp utan oxytocinbehandling ingick. I studien ingick 351 förstföderskor med normal graviditet varav totalt 108 av kvinnorna kom att ingå i de två randomiserade grupperna. Datainsamling och analys gjordes på förlossningsutfallet för mor och barn. Resultatet visade på skillnad mellan grupperna tidig eller uppskjuten oxytocinbehandling vad gällde förlossningslängden. Tidig oxytocinbehandling innebar i genomsnitt två timmar kortare förlossning. I samma grupp ingick det fler barn som inte fått tidig hud mot hud kontakt med modern jämfört med den sent randomiserade gruppen. Det fanns också en tendens till att kvinnorna med tidig oxytocinbehandling hade fler förlossningar som avslutades instrumentellt. Vätskeintag under förlossning skilde sig åt mellan kontrollgruppen och de två randomiserade grupperna. Slutsatser. Värksvaghet hos kvinnor med förlängt öppningsskede orsakar fler instrumentella förlossningar och fler påverkade barn. Förlossningsförlopp med konstaterad värksvaghet förkortas med tidig tillförsel av oxytocin men med en tendens till försämrat utfall för mor och barn bl.a. genom ökat antal instrumentella förlossningar och fler påverkade barn. Längre förlossningsförlopp och värksvaghet inträffar i högre grad för kvinnor med epiduralbedövning. Kvinnors vätskeintag under förlossning tycks ha viss påverkan på förlossningsförlopp. Sökord: Oxytocin, delivery, labour, labor, childbirth, labour arrest, augmentation of labour, labour outcome, epidural / The objectives were to compare the effects between early or delayed augmentation with oxytocin during lack of progress in labour and to study the outcome of labour in relation to the intake of oral fluid and/or infusions. Method. The design of the study was a prospective randomized controlled trial where comparison with controls without oxytocin was included. Three hundred and fifty one low-risk nulliparous women were included in the study in which a total number of one hundred and eight were randomly allocated to either of the two randomized groups. Data were collected and analyzed in relation to the outcome of delivery for mother and child. The results showed a difference concerning the length of labour between the two groups early and delayed oxytocin treatment. In the randomized group of early oxytocin treatment the mean shortage of the length of labour was two hours. The same group there was a lager number of children without early skin-to-skin contact with the mother immediately after birth compared to the group with delayed augmentation. The results of the study also indicated a tendency towards a higher frequency of caesarean sections and instrumental vaginal deliveries in the group of women receiving early oxytocin treatment. The amount of fluid intake during delivery differed between the two randomized groups and the controls. Conclusions. Delays in the progress of labour result in a higher frequency of caesarean sections and instrumental deliveries and more affected children. Delays in the progress of labour are shortened with early treatment of oxytocin but with a tendency for less favourable outcome for the mother and the child due to increased number of caesarean sections and instrumental deliveries and more affected children. Lack of progress in labour occurs more often in women using epidural analgesia. Women’s fluid intake during delivery seems to affect the course of labour. Keywords: Oxytocin, delivery, labour, labor, childbirth, labour arrest, augmentation of labour, labour outcome, epidural

<p>Syftet med studien var att jämföra effekterna mellan tidig eller uppskjuten oxytocinbehandling vid värksvaghet under förlossning samt att studera hur intaget av peroral vätska och/eller intravenös infusion kunde påverka förlossningsutfallet.</p><p>Metod en prospektiv randomiserad kontrollerad studie där även jämförelse med kontrollgrupp utan oxytocinbehandling ingick. I studien ingick 351 förstföderskor med normal graviditet varav totalt 108 av kvinnorna kom att ingå i de två randomiserade grupperna. Datainsamling och analys gjordes på förlossningsutfallet för mor och barn.</p><p>Resultatet visade på skillnad mellan grupperna tidig eller uppskjuten oxytocinbehandling vad gällde förlossningslängden. Tidig oxytocinbehandling innebar i genomsnitt två timmar kortare förlossning. I samma grupp ingick det fler barn som inte fått tidig hud mot hud kontakt med modern jämfört med den sent randomiserade gruppen. Det fanns också en tendens till att kvinnorna med tidig oxytocinbehandling hade fler förlossningar som avslutades instrumentellt. Vätskeintag under förlossning skilde sig åt mellan kontrollgruppen och de två randomiserade grupperna.</p><p>Slutsatser. Värksvaghet hos kvinnor med förlängt öppningsskede orsakar fler instrumentella förlossningar och fler påverkade barn. Förlossningsförlopp med konstaterad värksvaghet förkortas med tidig tillförsel av oxytocin men med en tendens till försämrat utfall för mor och barn bl.a. genom ökat antal instrumentella förlossningar och fler påverkade barn. Längre förlossningsförlopp och värksvaghet inträffar i högre grad för kvinnor med epiduralbedövning. Kvinnors vätskeintag under förlossning tycks ha viss påverkan på förlossningsförlopp.</p><p>Sökord: Oxytocin, delivery, labour, labor, childbirth, labour arrest,</p><p>augmentation of labour, labour outcome, epidural</p> / <p>The objectives were to compare the effects between early or delayed augmentation with oxytocin during lack of progress in labour and to study the outcome of labour in relation to the intake of oral fluid and/or infusions.</p><p>Method. The design of the study was a prospective randomized controlled trial where comparison with controls without oxytocin was included. Three hundred and fifty one low-risk nulliparous women were included in the study in which a total number of one hundred and eight were randomly allocated to either of the two randomized groups. Data were collected and analyzed in relation to the outcome of delivery for mother and child.</p><p>The results showed a difference concerning the length of labour between the two groups early and delayed oxytocin treatment. In the randomized group of early oxytocin treatment the mean shortage of the length of labour was two hours. The same group there was a lager number of children without early skin-to-skin contact with the mother immediately after birth compared to the group with delayed augmentation. The results of the study also indicated a tendency towards a higher frequency of caesarean sections and instrumental vaginal deliveries in the group of women receiving early oxytocin treatment. The amount of fluid intake during delivery differed between the two randomized groups and the controls.</p><p>Conclusions. Delays in the progress of labour result in a higher frequency of caesarean sections and instrumental deliveries and more affected children. Delays in the progress of labour are shortened with early treatment of oxytocin but with a tendency for less favourable outcome for the mother and the child due to increased number of caesarean sections and instrumental deliveries and more affected children. Lack of progress in labour occurs more often in women using epidural analgesia. Women’s fluid intake during delivery seems to affect the course of labour.</p><p>Keywords: Oxytocin, delivery, labour, labor, childbirth, labour arrest, augmentation of labour, labour outcome, epidural</p>

Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 151-164).

Thesis (Ph.D.) -- University of Texas at Arlington, 2009.