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An investigation into the effectiveness of the voluntary medical male circumcision programme amongst secondary school learners in Mazowe District, ZimbabweMakonese, Graduate 21 September 2018 (has links)
MAAS / Centre for African Studies / Zimbabwe launched the Voluntary medical male circumcision programme (VMMC) in November 2009, with the primary aim of curbing sexual transmitted infections (STI’s). In 2010, the district of Mazowe managed to adopt voluntary medical male circumcision programme to curb sexual transmitted infections. It is of concern that the voluntary medical male circumcision programme has been below expectations in Mazowe district. Hence, the aim of the study was to explore the effectiveness of the voluntary medical male circumcision programme among secondary school learners in Mazowe district. Furthermore, the primary goals of the study were firstly check the levels of understanding about the voluntary medical male circumcision programme among secondary school learners in Mazowe district. Secondly, explore the reasons behind the low rate of the voluntary medical male circumcision programme among secondary school learners. Thirdly, investigate whether cultural beliefs influence the learners’ choice. Lastly, recommend possible ways of improving the uptake of the voluntary medical male circumcision programme among secondary school learners in Mazowe district. A qualitative research method used in the study. Also, un-structured interviews and focused group discussions. The researcher conducted interviews using purposeful sampling method on three secondary schools in Mazowe district, Zimbabwe and about forty respondents participated in the study. The study adopted a planned behaviour and person/client centered approaches. The thesis’s conclusions deduced that most of the male respondents are not ready or willing to receive circumcision due to fear of being screened for HIV/AIDS, the cost of the procedure, pain, bleeding, to mention but a few. Furthermore, the researcher identified that in the Shona culture, medical male circumcision is rarely unknown. In addition, the Ministry of Health and Child Welfare must introduce new ways of circumcision to avoid bleeding, pain and must remove the screening of the HIV testing procedure before one is circumcise. Therefore, by these outcomes the Ministry of Child and Health Care Centre will try to find strategies in which they can scale the programme, since the study highlighted that most males are not going for circumcision, hence their lives are in predicament. More so, the study recommends
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that researchers must obtain consent and ethical clearance from different relevant place so that data there will not be harm to respondents. Also, there is a need to look for policies in which the government will use to assess strategies to scale the programme, since it is of paramount importance to test the VMMC programme about the impact that it is giving to the community and to find out whether it is helpful or not. More so, in terms of future researchers, there is a need to reconnoiter barriers that hinders males from circumcised. Hence, fourth, this will motivate number of District schools to bring awareness towards males to take part in the programme and prevent males from being susceptible to the infections as recommended by the WHO in 2007. In addition, decentralizing the programme to the community, stakeholders would be able to work hand in hand with the District to make sure that the rate of the VMMC is up and those males take part in the programme willingly. Hence, this will create an efficacy of the programme since all stakeholders and the community will scale up the programme since the priority of all sides will be to scale the programme. Furthermore, clearing misconceptions associated with male learners (witchcraft, pain, bleeding, and religion, to mention but the few), providing them with right mentality about the good side of the programme. In addition, there is a need for the Ministry of Health and Child Welfare to amend new polices that allows free male circumcision, especially in public hospitals, hence, through these amendments, males might be willing to get the services. Lastly but not least, the Department of Education in Zimbabwe must set up tight mechanism for assessment for the programme, especially at secondary and high schools. This will in turn, develop an effective assessment system to see how effective the programme is in the districts. Finally, it is of paramount importance that the National HIV/AIDS council collaborates with the Ministry of Health and Child Welfare in decentralizing the service of the VMMC, since some respondents were concerned that the distance to the service centers were a hindrance for circumcision. / NRF
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Optimisation de la performance en trail : étude des réponses cardiorespiratoires et des facteurs de la performance en course en montée vs descente / Optimizing trail running performance : cardiorespiratory responses and factors determining performance in downhill vs uphill runningLemire, Marcel 24 September 2019 (has links)
Il est bien établi chez les physiologistes, que si l’exercice de course en montée sollicite préférentiellement des contractions musculaires concentriques, l’exercice de course en descente requiert des actions musculaires frénatrices, majoritairement excentriques. L’exercice de course en descente à intensité sous-maximale génère un stimulus mécanique plus important pour un niveau de sollicitation métabolique moindre (i.e., V̇O2). Basée sur 3 études expérimentales, cette thèse de doctorat explore la physiologie spécifique de la course en déclivité, ainsi que ses prédicteurs physiologiques. Notre première étude montre une amplitude des réponses cardiorespiratoires amoindrie, une ventilation plus superficielle et une composante lente négative de consommation d’oxygène et de fréquence cardiaque en course en descente versus montée à vitesse constante et identique (8,5 km·h-1, pente de 15%). Lors de tests incrémentaux maximaux en course en descente vs montée vs plat, notre 2ème, partie A étude démontre que des coureurs bien entraînés, familiarisés avec la course en descente, peuvent atteindre FCmax, mais pas V̇O2max en descente. Lorsque les courses en descente et montée sont réalisées à même intensité métabolique (70% V̇O2max), notre 2ème (B) étude démontre que la course en descente (19 km·h-1, pente de -15%) induit des réponses cardiorespiratoires supérieures (FC et V̇E), une composante lente de V̇O2 significative et engendre une fatigue supérieure à la course en montée (6 km·h-1, pente de +15%). Enfin, une étude de terrain (étude 3) montre que les performances de 5 km de course en montée et en descente partagent quelques prédicteurs physiologiques communs (V̇O2max, force musculaire des membres inférieurs), bien que dans des proportions différentes. De plus, ces deux contre-la-montre sont également déterminés par des prédicteurs physiologiques spécifiques (i.e., raideur musculo-tendineuse en descente et indice de masse corporelle en montée). Nos résultats améliorent notre compréhension de la physiologie spécifique à la course en descente vs montée et ouvrent la voie des applications à l’entraînement des traileurs avec le but ultime d’optimiser leur performance. / It is admitted that uphill running mostly elicits concentric muscle actions whereas downhill running requires braking muscle actions inducing preferentially eccentric muscle action. Consequently, high running speed can be achieved in downhill (i.e., a high level of mechanical stress), despite low metabolic demands (i.e., low metabolic power). Using 3 experimental studies, this doctoral thesis explores the specific physiology of downhill vs uphill running as well as its physiological determinants. Our first study shows lower magnitude of the cardiorespiratory responses, a more superficial ventilation pattern and inverse V̇O2 and HR slow components in submaximal constant and same downhill vs uphill running velocity (8,5 km·h-1, 15% slope). During maximal incremental downhill vs uphill and level running, our study 2 part A demonstrates that well-trained endurance athletes, accustomed to downhill running, can reach maximal heart rate but not V̇O2max in downhill running. When downhill and uphill running are performed at similar metabolic demand (70% V̇O2max), our study 2 part B demonstrates that downhill running (19 km·h-1, -15% slope) elicits greater cardiorespiratory responses (HR and V̇E), a significant V̇O2 slow component and exacerbates muscle fatigue compared to uphill running (6 km·h-1, +15% slope). Finally, a field study (study 3) shows that 5-km downhill vs uphill running performances share some physiological predictors (V̇O2max, lower limb muscle strength) although in different proportions. In addition, this study also demonstrates that both time-trial performances are also determined by specific physiological predictors (i.e., musculotendinous stiffness for downhill and body mass index for uphill running). All in all, our results further our understanding of the specific physiology of downhill vs uphill running and open the way to training applications in trail runners with the ultimate goal to optimize trail running performance.
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Beeinflussung der intestinalen Folatresorption durch Umweltkontaminanten am Beispiel eines humanen in vitro ModellsNieke, Franziska 08 July 2014 (has links)
Folate sind als Überträger von C1-Fragmenten verschiedener Oxidationsstufen direkt an der Nukleinsäuresynthese beteiligt und spielen somit eine entscheidende Rolle im Zellstoffwechsel. So kann ein suboptimaler Folatstatus zur Ausprägung einer klinischen Symptomatik führen, die sich primär in Zellen mit hoher Teilungsrate manifestiert. Dabei gilt die megaloblastäre Anämie als Leitsymptom für einen akuten Folatmangel. Herausragende Bedeutung besitzen Folate in der Schwangerschaft, wo ihnen bei der Entwicklung des fetalen Nervensystems eine besondere Rolle zukommt. Bei einem zu niedrigen Serumfolatspiegel der Mutter steigt das Risiko für embryonale Missbildungen wie Neuralrohrdefekte stark an. Die weitere medizinische Relevanz der Folate steht momentan im Fokus der Forschung, wie z. B. der protektive Effekt in Bezug auf bestimmte Krebsformen, die Risikoreduktion für verschiedene kardiovaskuläre Erkrankungen sowie Zusammenhänge zwischen dem Folatstatus und neurologischen Störungen (Alzheimer, Depressionen). Allerdings kann Folat als essentielles Vitamin von Säugetieren nicht selbst synthetisiert werden, sondern muss aus externen Quellen über den Verdauungstrakt aufgenommen werden. Die Resorption aus dem Darm erfolgt nach aktuellem Kenntnisstand insbesondere über den Reduced Folate Carrier (RFC, SLC19A1) und den Proton-Coupled Folate Transporter (PCFT, SLC46A1). Trotz der Existenz dieser spezifischen Transporter ist der Folatmangel des Menschen der häufigste Vitaminmangel in Mitteleuropa. Er lässt sich durch eine ausschließlich ernährungsphysiologische Problematik nur unzureichend erklären. Interessanterweise besitzen sowohl das PCFT-Gen als auch das RFC-Gen in ihrer Promoterregion verschiedene Regulationselemente, unter anderem auch funktionell aktive DREs (Dioxin Response Element), die als Bindungsstelle für einen ligandenaktivierten Transkriptionsfaktor, den nukleären Arylhydrocarbon-Rezeptor (AhR), dienen. DREs wurden bisher hauptsächlich bei fremdstoffmetabolisierenden Enzymen wie z. B. Cytochrom P450-Isoenzymen gefunden und vermitteln bekanntermaßen die toxischen und karzinogenen Effekte von AhR-Liganden. Von besonderem Interesse sind in diesem Zusammenhang ubiquitär verbreitete Umweltkontaminanten wie die polyzyklischen und die halogenierten aromatischen Kohlenwasserstoffe (PAK, HAK), da sie in der Umwelt sehr persistent sind und sich dadurch in der Lebensmittelkette anreichern. Infolgedessen wurde im Rahmen dieser Studie der mögliche Einfluss von AhR-Liganden wie TCDD (2,3,7,8-tetrachlordibenzo-p-dioxin) und B[a]P (Benzo[a]pyren) auf die carriervermittelte intestinale Folatresorption beim Menschen untersucht sowie die Regulation der Transportproteine RFC und PCFT auf transkriptioneller Ebene experimentell überprüft. Als adäquates in vitro Modell diente dabei die humane Kolonzelllinie LS180, für die zunächst eine Charakterisierung erfolgte. Mittels RT-PCR wurde der Nachweis erbracht, dass alle am Folattransport beteiligten Import-und Exportcarrier auf mRNA-Ebene exprimiert werden. Für die Transportproteine RFC und PCFT erfolgte über den Western Blot auch der Nachweis auf Proteinebene. Die Funktionalität der AhR-Signalkaskade, die über methylcholanthrenartige Induktoren wie TCDD zur Induktion von Cytochrom P450 führt, konnte im Folgenden mittels Ethoxyresorufin-O-deethylase-Assay (EROD) überprüft werden. Es zeigte sich nach Induktion mit TCDD (0,01 - 10 nM) oder B[a]P (0,01 - 1 μM) über 12 – 96 h ein hochsignifikanter, dosis- und zeitabhängiger Effekt auf die Cyp1A1 vermittelte Enzymaktivität der Ethoxyresorufin-O-deethylase in den LS180-Zellen. Dabei konnten ligandenabhängige Unterschiede im Induktionsmuster ermittelt werden. Im Anschluss wurde im intestinalen Zellmodell die initiale konzentrations- und zeitabhängige Folataufnahme bei pH 5.5 über funktionelle Aufnahmeversuche mit Tritium-markierter Folsäure untersucht und charakterisiert. Sie stellte sich als aktiver, sättigbarer Prozess dar, wobei in den unbehandelten LS180-Zellen ca. eine Verdreifachung der intrazellulären Radioaktivität über einen Zeitraum von 2,5 min beobachtet werden konnte. Als kinetische Parameter wurden ein Km-Wert von 27,91 μM sowie ein Vmax-Wert von 281,2 pmol/min berechnet. Nachfolgende Untersuchungen mit den spezifischen Inhibitoren Raltitrexed (RTX) und Pemetrexed (PMX) konnten zeigen, dass sowohl PCFT als auch RFC an der funktionellen Folsäureaufnahme bei einem pH-Wert von 5.5 in dem gewählten Versuchsaufbau beteiligt sind. Der RFC scheint jedoch einen etwas höheren Anteil an der Gesamtaufnahme zu haben als der PCFT. In LS180-Zellen, die vorher mit den Modellsubstanzen TCDD (1 bzw. 10 nM) oder B[a]P (0,1 bzw. 1 μM) über 24 - 120 h inkubiert wurden, konnte eine zeit- und dosisabhängige, statistisch signifikante Reduktion der carriervermittelten Folatresorption beobachtet werden, wobei die maximale Verminderung der Aufnahmerate ca. 75 % betrug. Da sich dieser Effekt durch die AhR-Antagonisten Salicylamid (SAL) und CH-223191 (CH) dosisabhängig umkehren ließ, erfolgt die Regulation vermutlich über den AhR-Signalweg. Um den Mechanismus der Regulation zu klären, wurde mit Hilfe der quantitativen qRT-PCR unter Verwendung von TaqMan-Sonden die Genexpression von RFC und PCFT nach Vorbehandlung mit 1 - 10 nM TCDD oder 0,1 – 1 μM B[a]P über 12 - 120 h untersucht. Analog zu den Aufnahmeversuchen konnte hier eine zeit- und dosisabhängige Reduktion beider Transporter auf transkriptioneller Ebene beobachtet werden. Auch führte eine Vorbehandlung mit CH und SAL wiederum zu einer Umkehr des Effektes, wobei CH wahrscheinlich einen ligandenselektiven AhR-Antagonisten darstellt. Zusammenfassend konnte durch die vorliegende Arbeit nachgewiesen werden, dass Cytochrom P450-Induktoren über die AhR-Signalkaskade die carriervermittelte Folatresorption in humanen Kolonzellen herabregulieren. Es erscheint anhand der gewonnen Erkenntnisse möglich, dass die Folathomoöstase durch verschiedene Umweltkontaminanten wie z. B. TCDD negativ beeinflusst werden kann und als Folge daraus auch eventuell der Folatmangel der Bevölkerung in Industrienationen zumindest teilweise erklärbar wird. Es ist darüber hinaus denkbar, dass auch andere Fremdstoffe die Folataufnahme beeinflussen, da große planare Strukturen häufig über den AhR-Weg wirken. Weiterführende Studien sind notwendig, um das Verständnis für den Einfluss von Umweltkontaminanten auf die intestinale Folataufnahme zu verbessern.
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The rolling resistances of roller skis and their effects on human performance during treadmill roller skiingAinegren, Mats January 2010 (has links)
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
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Study of Argon Shrouding in Ingot Casting, with Focus on Improving the Operation at Scana Björneborg Steel PlantGhazian Tafrishi, Babak January 2014 (has links)
This thesis has been carried out as a development project at Scana Steel Björneborg with the purpose to study the influential parameters in argon shrouded ingot casting during the manufacturing of low-alloy steels. In the first stage, a literature study was conducted in order to investigate the theoretical background of the procedure and the importance of protecting the melt during ingot casting. Next, a computer model of the shield was designed using COMSOL Multiphysics® with regard to the process conditions at Scana Steel Björneborg. The effect of various parameters on the process was examined through simulations of the argon gas flow pattern, heat transfer between the gas and the melt stream, and the chemical species transport in the gas around the melt stream. Based on the simulation results, two different shapes of shield were proposed for the argon shrouding operation. A set of implementation tests was executed in order to check the installation and usage conditions of the two new shields. After deciding the proper shape of the shield, a full-scale ingot-casting test was performed with the selected shield to investigate the protection behavior. Moreover, the impact of the new casting-protection shield on the nitrogen and oxygen contents of steel was examined through sampling and analyzing the steel before and after casting. It was found that the use of the new shield during the uphill ingot casting is an effective way to reduce the final nitrogen and oxygen contents of the casted ingot. Therefore, the new design of the shield can be used as a developed substitute for the protection of the melt stream in the ingot casting operation.
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Der Einfluss von Repin1 auf die Fettzellgröße und den Glukosetransport in Adipozyten: Der Einfluss von Repin1 auf die Fettzellgrößeund den Glukosetransport in AdipozytenIlles, Monica 17 November 2011 (has links)
An der Spitze der Morbiditäts - und Mortalitätsstatistik steht weltweit das
Metabolische Syndrom, bestehend aus androider Adipositas, pathologischer
Glukosetoleranz, Dyslipidämie und arterieller Hypertonie, verbunden mit einer
erhöhten Inzidenz atherosklerotischer Gefäßerkrankungen. Der Replikationsinitiator
1 (Repin1) wurde kürzlich als mögliches Kandidatengen für Adipositas sowie damit
verbundene metabolische Funktionsstörungen in kongenen sowie subkongenen
Rattenstämmen identifiziert. Ziel der Arbeit war es, den Einfluss von Repin1 auf den
Fettzellstoffwechsel zu untersuchen. Hierfür wurde die Expression von Repin1 in 3T3–
L1 Präadipozyten und differenzierten 3T3-L1 Adipozyten mittels siRNA Technologie
stark vermindert, um so auf mögliche Funktionen des Proteins schließen zu können.
Nachfolgend wurden Veränderungen des Zellstoffwechsels mittels Glukosetransport,
Palmitataufnahme sowie Triglyceridgehalt der Adipozyten untersucht.
Repin1 wird in der 3T3-L1 Zelllinie exprimiert und zeigt eine steigende Expression
während der Adipogenese. Der Knockdown von Repin1 resultierte in kleineren
Fettzellen mit geringerer basaler, jedoch verstärkter insulinstimulierter
Glukoseaufnahme. Auch der Fettstoffwechsel zeigte sich alteriert: Neben einer
reduzierten Palmitataufnahme war die Expression verschiedener Schlüsselgene der
Fetttropfenfusion, des Glukose-sowie des Fetttransportes verändert.
Fazit: Repin1 reguliert die Expression von Genen, die eine Rolle bei der Festlegung der
Fettzellgröße und des basalen und Insulin-stimulierten Glukosetransports in
Adipozyten spielen.:Inhaltsverzeichnis I
Vorbemerkung II
Wissenschaftlicher Anteil des Promovenden an der Publikation III
Bibliographische Beschreibung IV
Abkürzungsverzeichnis V
I. Einleitung - Das metabolische Syndrom 1
A. Definition und Prävalenz 1
B. Klinische Relevanz 2
C. Pathophysiologie 3
D. Exogene und genetische Faktoren 7
II. Der Replikationsinitiator 1 9
III. Zielstellung der Arbeit 11
IV. Publikation 12
V. Zusammenfassung 19
VI. Supplemental Materials 24
VII. Literaturverzeichnis 32
VIII. Eigenständigkeitserklärung 38
IX. Curriculum vitae 39
X. Veröffentlichungen im Rahmen dieser Arbeit 41
XI.Danksagung 42
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Exploiting the genetic diversity of rapeseed (Brassica napus L.) root morphology to improve nitrogen acquisition from soilLouvieaux, Julien 12 October 2020 (has links) (PDF)
Nitrogen (N) is a central nutrient in cropping systems. However, a considerable N fraction is lost through runoffs and leaching with detrimental consequences for environment and controversial effects on human health. Increasing the plant N uptake by optimizing the degree of root branching for exploring a larger soil volume in search of the mobile nitrate resource may contribute to limit soil leaching and subsequently to rely more efficiently on the soil mineralization and fertilizer inputs. Rapeseed (Brassica napus L.) is a major oil crop that highly depends on N fertilization. This doctoral thesis aims at exploring the diversity of root morphology in recently selected cultivars and in a large set of rapeseed inbred lines, and at understanding the genetic control on root morphology and how it is impacted by N nutrition.Firstly, a panel of twenty-eight European recently selected cultivars of winter oilseed rape were tested in laboratory and field conditions. Upon hydroponic culture, these hybrids showed a great diversity for biomass production and root morphological traits. Differences in root and shoot dry biomasses and lateral root length were mainly explained by the genotype, while differences in primary root length by the nutrition. The cultivars were tested in a pluriannual field trial. The observed variation for yield and seed quality traits attributed to the genotype was more important than the year or the genotype x year interaction effects. The total root length measured in laboratory could predict the proportion of nitrogen taken-up from the field and reallocated to the seeds. The genetic interrelationship between cultivars, established with polymorphic markers, indicated a very narrow genetic base. Positive correlations were found between the genetic distance measures, root morphological trait distances during nitrogen depletion conditions, and agronomic performance. Secondly, three cultivars previously selected from a root morphology screen at a young developmental stage were field tested with two nitrogen applications. The purpose was to examine the relationship between root morphology and Nitrogen Uptake Efficiency (NUpE) and to test the predictiveness of canopy optical indices for seed quality and yield. A tube-rhizotron system was used to incorporate below-ground root growth information. One-meter length clear tubes were installed in soil at an angle of 45°. The root development was followed with a camera at key growth stages in autumn (leaf development) and spring (stem elongation and flowering). Autumn was a critical time window to observe the root development and exploration in deeper horizons (36-48 cm) was faster without any fertilization treatment. Analysis of the rhizotron images was challenging and it was not possible to clearly discriminate between cultivars. Canopy reflectance and leaf optical indices were measured with proximal sensors. The Normalized Difference Vegetation Index (NDVI) was a positive indicator of biomass and seed yield while the Nitrogen Balance Index (NBI) was a positive indicator of above-ground biomass N concentration at flowering and seed N concentration at harvest.Thirdly, the natural variability offered by a diversity set of 392 inbred lines was screened to apprehend the genetic control of root morphology in rapeseed and how it is impacted by nitrogen nutrition. Seedlings grew hydroponically with low (0.2 mM) or elevated (5 mM) nitrate supplies. Low nitrate supply triggered the primary root and lateral root growth, while elevated supply promoted shoot biomass production. A considerable variation degree in the root morphological traits was observed across the diversity set, and there was no trade-off between abundant lateral root branching and shoot biomass production. Root traits were mainly dependent on the genotype and highly heritable. A genome wide association study identified some genomic regions associated with biomass production and root morphological traits. A total of fifty-nine QTLs were identified and thirty of them were integrated into seven clusters on chromosomes A01 and C07. Some candidate genes were identified with Arabidopsis orthologs related to root growth and development, nitrogen nutrition or hormone regulation.This study provides promising routes for redesigning the root system architecture by uncovering nitrogen-interactive genomic regions shaping root morphology. A perspective is to develop genetic markers associated with root morphological traits that could be used for assisted breeding. / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
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Effets de l’ovariectomie et de l’activité physique sur l’homéostasie du glucose chez les rates ZDFMentor, Junior S. 06 1900 (has links)
No description available.
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Advisory Committee on Immunization Practices Recommendations, Socioeconomics, Demographics, and Influenza Vaccine UptakeGadarowski, Jennifer 01 January 2019 (has links)
Seasonal influenza outbreaks are associated with morbidity and mortality in the United States. Though children are the most susceptible to influenza infection and are most likely to transmit the illness to others, many children are not vaccinated. The purpose of this study was to examine the relationship between seasonal influenza vaccination Advisory Committee on Immunization Practices (ACIP) recommendations, demographic characteristics, socioeconomic factors, and vaccine type among children over 3 consecutive flu seasons. This quantitative cross-sectional study was guided by the social ecology of health model. Secondary data from 3 consecutive flu seasons (2014-2015, 2015-2016, and 2016-2017) provided by the National Health Interview Survey was used for this study. Binary logistic regression and chi-square were used to analyze the data. A relationship between socioeconomic status, demographics (age, race, and family income) and vaccine type (live-attenuated influenza vaccine [LAIV]/inactivated influenza vaccine) was established among U.S. children; those who received LAIV were most likely to be White elementary school age children with a higher family income. Demographic and socioeconomic status was not considered influential in LAIV uptake for race, health insurance status, or family income. ACIP recommendations by age and year had the greatest impact on flu vaccine choice for this sample population. The results of this study can lead to social change by providing information for policy that can increase vaccine uptake, which can result in lower health cost and reduced illness and death rates associated with the flu, especially for those most at risk.
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Investigating the Impact of Teacher-given Formative Feedback in ESL Draft Writing / : Undersökning om inverkan av lärares formativa återkoppling till uppsatsutkasts i engelska som andraspråkPalm, Marcus January 2022 (has links)
This paper examines the impact of teachers' formative feedback on intermediate drafts on student writing development and its interrelationship with summative assessment. Formative feedback is advocated for its benefits on learners writing development; however, its usage in writing instruction at the upper-secondary level is met with frustrations from teachers and students alike. This paper endeavors to draw upon international research on the topic, synthesize the results and correlate it to the educational context of ESL teaching of writing in Swedish upper-secondary schools to elucidate what formative feedback practices are beneficial and how summative aspects can impact them. Research shows that feedback that is encouraging, investigative, and deals with global and local issues alike is more beneficial for facilitating writing development in a new genre. However, teachers should be mindful of overusing imperatives as they can act as demotivators, and they should also be mindful of the toll engaging with feedback takes on learners. Furthermore, teachers should not use grades to motivate feedback uptake, as it does not incentivize learners to do meaningful revisions. Lastly, more research should examine how formative feedback can illustrate students' writing standards without impeding benefits to writing development.
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