<p>Modern ski-treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical performance in a laboratory environment using classical and freestyle techniques on roller skis. For elite athletes the differences in performance between test occasions are quite small, thus emphasising the importance of knowing the roller skis’ rolling resistance coefficient, µ_R, in order to allow correct comparisons between the results, as well as providing the opportunity to study work economy between different athletes, test occasions and core techniques.</p><p>Thus, one of the aims of this thesis was to evaluate how roller skis’ µ_R is related to warm-up, mass, velocity and inclination of the treadmill. It was also necessary to investigate the methodological variability of the rolling resistance measurement system, RRMS, specially produced for the experiments, with a reproducibility study in order to indicate the validity and reliability of the results.</p><p>The aim was also to study physiological responses to different µ_R during roller skiing with freestyle and classical roller skis and techniques on the treadmill as a case in which all measurements were carried out in stationary and comparable conditions.</p><p>Finally, the aim was also to investigate the work economy of amateurs and female and male junior and senior cross-country skiers during treadmill roller skiing, i.e. as a function of skill, age and gender, including whether differences in body mass causes significant differences in external power per kg due to differences in the roller skis’ µ_R.</p><p>The experiments showed that during a warm-up period of 30 minutes, µ_R decreased to about 60-65% and 70-75% of its initial value for freestyle and classical roller skis respectively. For another 30 minutes of rolling no significant change was found. Simultaneous measurements of roller ski temperature and m_R showed that stabilized m_R corresponds to a certain running temperature for a given normal force on the roller ski. The study of the influence on m_R of normal force, velocity and inclination produced a significant influence of normal force on m_R, while different velocities and inclinations of the treadmill only resulted in small changes in m_R. The reproducibility study of the RRMS showed no significant differences between paired measurements with either classical or the freestyle roller skis.</p><p>The study of the effects on physiological variables of ~50% change in µ_R,showed that during submaximal steady state exercise, external power, oxygen uptake, heart rate and blood lactate were significantly changed, while there were non significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed and this occurred without a significantly changed maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion was non significant or small.</p><p>The final part of the thesis, which focused on work economy, found no significant difference between the four groups of elite competitors, i.e. between the two genders and between the junior and senior elite athletes. It was only the male amateurs who significantly differed among the five studied groups. The study also showed that the external power per kg was significantly different between the two genders due to differences in body mass and m_R, i.e. the lighter female testing groups were roller skiing with a relatively heavier rolling resistance coefficient compared to the heavier testing groups of male participants.</p> / Sporttech

Modern ski-treadmills allow cross-country skiers, biathletes and ski-orienteers to test their physical performance in a laboratory environment using classical and freestyle techniques on roller skis. For elite athletes the differences in performance between test occasions are quite small, thus emphasising the importance of knowing the roller skis’ rolling resistance coefficient, µR, in order to allow correct comparisons between the results, as well as providing the opportunity to study work economy between different athletes, test occasions and core techniques. Thus, one of the aims of this thesis was to evaluate how roller skis’ µR is related to warm-up, mass, velocity and inclination of the treadmill. It was also necessary to investigate the methodological variability of the rolling resistance measurement system, RRMS, specially produced for the experiments, with a reproducibility study in order to indicate the validity and reliability of the results. The aim was also to study physiological responses to different µR during roller skiing with freestyle and classical roller skis and techniques on the treadmill as a case in which all measurements were carried out in stationary and comparable conditions. Finally, the aim was also to investigate the work economy of amateurs and female and male junior and senior cross-country skiers during treadmill roller skiing, i.e. as a function of skill, age and gender, including whether differences in body mass causes significant differences in external power per kg due to differences in the roller skis’ µR. The experiments showed that during a warm-up period of 30 minutes, µR decreased to about 60-65% and 70-75% of its initial value for freestyle and classical roller skis respectively. For another 30 minutes of rolling no significant change was found. Simultaneous measurements of roller ski temperature and mR showed that stabilized mR corresponds to a certain running temperature for a given normal force on the roller ski. The study of the influence on mR of normal force, velocity and inclination produced a significant influence of normal force on mR, while different velocities and inclinations of the treadmill only resulted in small changes in mR. The reproducibility study of the RRMS showed no significant differences between paired measurements with either classical or the freestyle roller skis. The study of the effects on physiological variables of ~50% change in µR,showed that during submaximal steady state exercise, external power, oxygen uptake, heart rate and blood lactate were significantly changed, while there were non significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed and this occurred without a significantly changed maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion was non significant or small. The final part of the thesis, which focused on work economy, found no significant difference between the four groups of elite competitors, i.e. between the two genders and between the junior and senior elite athletes. It was only the male amateurs who significantly differed among the five studied groups. The study also showed that the external power per kg was significantly different between the two genders due to differences in body mass and mR, i.e. the lighter female testing groups were roller skiing with a relatively heavier rolling resistance coefficient compared to the heavier testing groups of male participants. / Sporttech

This paper describes efforts to optimize the parameters for a platoon identification and accommodation algorithm that minimizes vehicle emissions. The algorithm was developed and implemented in the AnyLogic framework, and was validated by comparing it to the results of prior research. A four-module flowchart was developed to analyze the traffic data and to identify platoons. The platoon end time was obtained from the simulation and used to calculate the offset of the downstream intersection. The simulation calculates vehicle emissions with the aid of the VT-Micro microscopic emission model. Optimization experiments were run to determine the relationship between platoon parameters and minimum- and maximum-emission scenarios. Optimal platoon identification parameters were found from these experiments, and the simulation was run with these parameters. The total time of all vehicles in the simulation was also found for minimum and maximum emissions scenarios. Time-space diagrams obtained from the simulations demonstrate that optimized parameters allow all cars to travel through the downstream intersection without waiting, and therefore cause a decrease in emissions by as much as 15.5%. This paper also discusses the outcome of efforts to leverage high resolution data obtained from WV-705 corridor in Morgantown, WV. The proposed model was developed for that purpose and implemented in the AnyLogic framework to simulate this particular road network with four coordinated signal-controlled intersections. The simulation was also used to calculate vehicle CO, HC, NOx emissions with the aid of the VT-Micro microscopic emission model. Offset variation was run to determine the optimal offsets for this particular road network with traffic volume, signal phase diagram and vehicle characteristics. A classifier was developed by discriminant analysis based on significant attributes of HRD. Equation of this classifier was developed to distinguish between set of timing plans that produce maximum emission from set of timing plans that produce maximum emission. Also, current work investigates the potential use of the GPS-based and similar priority systems by giving preemption through signalized intersections. Two flowcharts are developed to consider presence of emergency vehicle (EV) in the system so called EV life cycle and EV preemption (EVP). Three scenarios are implemented, namely base case scenario when no EV is involved, EV scenario when EV gets EVP only, and EV scenario when EV gets preemption by signals and right-of-way by other vehicles. Research makes an attempt to compare emission results of these scenarios to find out whether EV effects vehicle emission in the road network and what is the level of this influence if any. / Master of Science

The aim of this thesis was to investigate roller ski characteristics; classical and freestyle roller skis’ rolling resistance coefficients (μR) and classical style roller skis’ static friction coefficients (μS), and to study the influence of different μR and μS on cross-country skiers’ performance and both physiological and biomechanical indices. The aim was also to study differences in skiing economy and efficiency between recreational skiers, female and male junior and senior elite cross-country skiers.The experiments showed that during a time period of 30 minutes of rolling on a treadmill (warm-up), μR decreased significantly (p&lt;0.05) to about 60-65 % and 70-75 % of its initial value for freestyle and classical roller skis respectively. Also, there was a significant influence of normal force on μR, while different velocities and inclinations of the treadmill only resulted in small changes in μR.The study of the influence on physiological variables of a ~50 % change in μR showed that during submaximal steady rate exercise, external power, oxygen uptake, heart rate and blood lactate were significantly changed, while there were non-significant or only small changes to cycle rate, cycle length and ratings of perceived exertion. Incremental maximal tests showed that time to exhaustion was significantly changed and this occurred without a change in maximal power, maximal oxygen uptake, maximal heart rate and blood lactate, and that the influence on ratings of perceived exertion was non-significant or small.The study of classical style roller skis μS showed values that were five to eight times more than the values of μS reported from on-snow skiing with grip-waxed cross-country skis.The subsequent physiological and biomechanical experiments with different μS showed a significantly lower skiing economy (~14 % higher v̇O2), higher heart rate, lower propulsive forces coming from the legs and shorter time to exhaustion (~30 %) when using a different type of roller ski with a μS similar to on-snow skiing, while there was no difference between tests when using different pairs of roller skis with a (similar) higher μS.The part of the thesis which focused on skiing economy and efficiency as a function of skill, age and gender, showed that the elite cross-country skiers had better skiing economy and higher gross efficiency (5-18 %) compared with the recreational skiers, and the senior elite had better economy and higher efficiency (4-5 %) than their junior counterparts, while no differences could be found between the genders. / Syftet med denna avhandling var att undersöka fristils- och klassiska rullskidors rullmotståndskoefficienter (μR) och klassiska rullskidors statiska friktionskoefficienter (μS) samt effekter av olika μR och μS på längdskidåkares prestation vid rullskidåkning på rullande band. Syftet var även att undersöka s.k. åkekonomi och mekanisk verkningsgrad mellan motionärer och kvinnliga och manliga junior- och seniorlängdskidåkare på elitnivå.Experimenten visade att under en period av 30 minuters kontinuerligt rullande, på rullande band, så sjönk μR signifikant (p&lt;0.05) till 60-65 % och 70-75 % av initiala värden, för fristils- respektive klassiska rullskidor. Undersökandet av olika normalkrafter, hastigheter och lutningars påverkan på μR resulterade i en signifikant, negativ korrelation för μR som funktion av normalkraft, medan olika hastigheter och lutningar endast medförde små förändringar av μR.Studien som undersökte fysiologiska effekter av olika μR visade, vid submaximala konstanta arbetsbelastningar, att yttre effekt, syreupptagning, hjärtfrekvens och blodlaktat förändrades signifikant vid ~50 % förändring av μR. Försökspersonernas frekvens och sträcka per frekvens samt skattning av upplevd ansträngning resulterade dock i mestadels icke signifikanta eller små förändringar. Protokollen med successivt ökande arbetsbelastning (maxtest) resulterade i signifikant förändrad tid till utmattning, vid ~50 % förändring av μR. Detta inträffade utan signifikant skillnad i maximal syreupptagning, hjärtfrekvens och blodlaktat, vilket även mestadels gällde för skattning av upplevd ansträngning.Experimenten som undersökte klassiska rullskidors μS visade att dessa erhöll värden som är fem till åtta gånger högre än vad som rapporterats från studier av μS på snö med fästvallade skidor.Den efterföljande studien som undersökte fysiologiska och biomekaniska influenser av olika μS visade, vid submaximala konstanta arbetsbelastningar, att åkekonomin försämrades (~14 % högre syreförbrukning), hjärtfrekvensen ökade, den framåtdrivande kraften från benen på rullskidorna minskade samt att det blev kortare tid till utmattning (~30 %), vid maxtest, när skidåkarna använde rullskidor med en μS i likhet med vad som rapporterats för skidåkning på snö. För arbetsförsöken med olika rullskidor av olika fabrikat med en högre, och likartad, μS förelåg ingen skillnad i de undersökta variablerna.Studien som undersökte åkekonomi och mekanisk verkningsgrad som funktion av prestationsnivå, ålder och kön, visade att elitskidåkarna hade bättre åkekonomi och verkningsgrad (5-18 %) i jämförelse med motionärerna, att seniorerna hade bättre åkekonomi och verkningsgrad (4-5 %) än juniorerna och att ingen skillnad kunde konstateras mellan könen.

Treatment success in IVF-ICSI is mainly limited by female age, but differences in ovarian reserve (OR; the remaining pool of oocytes and their quality) between individuals modify treatment prerequisites among women of similar age. OR may be assessed by OR tests (ORTs). The main aims of this work were to study menstrual cycle length (MCL), basal levels of circulating gonadotrophins, antral follicle count (AFC) and serum Anti-Müllerian hormone (AMH) levels and their associations with and prognostic capacities regarding IVF-ICSI outcome in large cohorts of unselected women. Age-adjusted MCL was positively and linearly associated with pregnancy rates (PRs), live-birth rates (LBRs) and ovarian response to controlled ovarian hyperstimulation. An MCL of &gt;34 days almost doubled the LBR compared with an MCL of &lt;26 days. The grouped variable ‘combined FSH and LH levels’ was superior to both individual gonadotrophin levels and the LH:FSH ratio. The highest mean PR was seen in connection with a combination of FSH &lt;6.7 U/l with LH &gt;4.9 U/l; PRs were lowest when FSH-LH levels were opposite to this (high-low) and intermediate when FSH-LH levels were low-low or high-high. Associations with LBR and ovarian response were similar as those for PR. AFCs and serum AMH levels were positively and log-linearly associated with PR, LBR and ovarian response. Success rates levelled out above AFC 30 or AMH 5 ng/ml. Treatment outcome was superior among women with polycystic ovaries. Among the studied ORTs, logAFC and logAMH concentration correlated most strongly. After multivariate testing, entering all studied ORTs, AMH and female age remained independently associated with LBR. AMH + AFC + age predicted both poor and excessive ovarian responses with high accuracy. Adjusting for age and oocyte yield, all ORTs remained significant for LBR, implying that ORTs also capture information on oocyte quality. In conclusion, measures of OR are strongly associated with PR, LBR and ovarian response in a log-linear fashion, and partly reflect oocyte quality. The OR spectrum is continuous, from small ‘oligofollicular’ ovaries (the low extreme) to polycystic ovaries (the high extreme). Among the studied ORTs, AMH together with age provide the most powerful basal estimate for IVF/ICSI outcome.

Las características antropométricas, del material de competición y la evolución de las variables cinemáticas (velocidad, frecuencia, longitud e índice de ciclo) sobre las distancias de 200 y 500 m, se valoraron en un total de 131 piragüistas de 13 y 14 años (hombres kayakistas, mujeres kayakistas y hombres canoistas, agrupados por edad). En la mayoría de las medidas antropométricas, los hombres kayakistas de 14 años fueron superiores al resto de categorías, no encontrándose diferencias entre los grupos de mujeres. La evolución de las variables cinemáticas fue similar en las diferentes categorías y distancias, con una tendencia decreciente de la velocidad y del índice de ciclo a partir de los primeros 50 m, una estabilización de la longitud de ciclo a partir de esta distancia y una disminución progresiva de la frecuencia de ciclo desde el inicio de la prueba. / The anthropometric characteristics, set-up of competition equipment and evolution of the kinematic variables (speed, cycle frequency, cycle length and cycle index) over distances of 200- and 500-m were analysed in 131 paddlers (male kayakers, women kayakers and male canoeists; 13-14 years-old). In most of the anthropometric measurements, 14 year-old male kayakers were higher than other groups; no differences were found between female groups. The evolution of the kinematic variables was similar in the different categories and distances. The speed and cycle index decreased through the test after the first 50 m, while the cycle length was stable. The cycle frequency had a progressive decrease along the distance

La domestication du mil (Pennisetum glaucum), dans le Sahel, a engendré une large gamme de variétés, très diversifiées pour de nombreuses caractéristiques agronomiques. En particulier, la diversité de la durée du cycle des variétés locales de mil est une composante essentielle des stratégies mises en œuvre par les agriculteurs pour faire face aux fluctuations des précipitations et assurer une certaine stabilité de la production. Au cours des dernières décennies, des évolutions dans les pratiques agricoles ont été observées, en réponse à des changements écologiques et sociaux. Une des conséquences de ces évolutions pourrait être l’existence de flux de gènes entre variétés à cycle court et variétés à cycle long du fait de l’émergence de situations de parapatrie entre ces deux types de variétés, naguère isolées. Par ailleurs, l’existence de recouvrement des périodes des floraisons de ces deux types variétaux a déjà été préalablement observée. Une telle situation amène donc à s’interroger sur la dynamique évolutive passée et actuelle de la diversité de la longueur du cycle du mil dans le Sahel. Dans la première partie de ma thèse, j’ai évalué les possibilités d’occurrence de flux de gènes entre variétés précoces et tardives de mil dans le Sud-ouest du Niger, en utilisant une approche comparative entre situations contrastées pour la distribution spatiale de ces deux types de variétés. J’ai réalisé : 1) une étude des périodes de floraison de deux variétés de mil (précoce (Haïni Kiré) : 75 à 95 jours entre le semis et la maturité et tardive (Somno) : 105 à 125 jours de durée de cycle) dans plusieurs champs paysans, et dans deux villages. 2) une analyse moléculaire à l’aide de 15 marqueurs microsatellites qui a permis l’estimation des niveaux de différenciation génétique entre populations de mils précoces et tardifs échantillonnés dans 4 villages (incluant les deux villages déjà cités) de la même région.Les résultats ont montré la possibilité effective de flux de pollen et l’existence d’introgressions génétiques entre variétés précoces et tardives. Les mécanismes qui pourraient permettre un maintien sur le long terme d’une différenciation phénologique entre les deux types variétaux malgré l’existence de ces flux de gènes, sont discutés.Dans la deuxième partie, j’ai utilisé une approche « gène candidat » combinée à une démarche de génétique des populations, pour tenter d’identifier des gènes qui auraient pu contribuer à la diversité de la durée de cycle chez le mil. Je me suis focalisé sur trois gènes du contrôle de la transition florale PgHd3a, PgDwarf8 et PgPHYC. Leur implication dans la diversité de la durée de cycle chez plusieurs espèces a déjà été montrée. J’ai estimé les niveaux de différenciation génétique entre les mils domestiques et sauvages, précoces et tardifs pour ces trois gènes J'ai aussi cherché à mettre en évidence, au sein de ces gènes, les empreintes éventuelles d’évènements sélectifs passés. Afin de prendre en compte l’histoire démographique des mils dans les tests de neutralité sélective, j’ai utilisé les données de polymorphisme nucléotidiques de 8 séquences témoins dans le cadre d’une approche Bayésienne.Les résultats obtenus suggèrent fortement que PgHd3a et PgDwarf8 ont été ciblés par la sélection durant la domestication. Cependant, les données ne soutiennent pas l’hypothèse d’un rôle potentiel des trois gènes candidats dans la différenciation de la durée de cycle entre les variétés locales précoces et tardives. L’approc / Domestication of pearl millet (Pennisetum glaucum) in the Sahel of Africa has produced a wide range of diversity in cycle duration of landraces. This diversity allows Sahelian farmers to outface the precipitation fluctuation and to ensure regularity in grain production. Due to ecological and social recent changes, modifications of farmer’s practices could be a factor promoting gene flow between the early and late flowering varieties by increasing the opportunity of neighboring and flowering overlap between them. Such a situation raises questions about the past and current evolutionary dynamics of phenological diversity in this crop.In the first part of my thesis I tried to evaluate the possibility of gene flow between pearl millet varieties in South-West Niger, through a comparative approach among contrasting situations pertaining to the spatial distribution of early and late landraces. Therefore I conducted: 1) a field study where we observed flowering periods, for two types of varieties (early type (Haïni Kiré): 75 to 95 days and late type (Somno): 105 to 125 days of cycle length) in several pearl millet fields, and in two villages 2) a molecular study that allows the assessment of the level of genetic differentiation between late and early flowering populations sampled from four villages (including the two where the field study was conducted) of the same region (Dallol Bosso), using microsatellite markers. I was able to demonstrate the occurrence of pollen flow between the two types of landraces and I also showed evidence of genetic introgression between early and semi-late landraces. Potential mechanisms that would allow for the maintenance of the phenological differentiation between these two varieties and despite the gene flow are discussed.In the second part of this work I used a candidate gene and a population genetics approach, to try to identify genes that may have contributed to the cycle length diversity in pearl millet. I focused on three flowering candidate genes, PgHd3a, PgDwarf8 and PgPHYC which have been shown to be involved in the cycle length genetic diversity in several species, in order to estimate the differentiation between wild and domestic pearl millets and between early and late landraces, on the basis of theses candidate genes. I also tried to track for the fingerprint of eventual past selective events within these candidate genes. To be able to distinguish the effects of selection from the effect of demographic events that occurred during the domestication process, I used 8 neutral STS loci and an Approximate Bayesian Computation approach.My results strongly suggest that PgHd3a and PgDwarf8 were likely targeted by selection during domestication. However, a potential role of any of the three candidate genes in the phenological differentiation between early and late landraces was not supported by our data. The Bayesian approach confirmed the idea, suggested by many authors, that the gene flow from the wild to the domestic genetic pool has contributed significantly to the genetic diversity of the domestic pearl millet.