169 research outputs found
Relationship between Aspalathus linearis (Burm. F.) R. Dahlgren (rooibos) growth and soil moisture in a glasshouse and in the DSSAT-CSM crop model
Get PDFClimate change and drought pose a major threat to agriculture and water resources globally and for rooibos (Aspalathus linearis (Burm. F.) R. Dahlgren) production in the Western Cape province of South Africa. Rooibos is adapted to the coarse, nutrient poor, acidic, well-drained, deep sandy soil of the Fynbos biome. The region has a Mediterranean climate, which is characterised by wet cold winters, with an average annual rainfall of about 375 mm, and dry summers. The growth of rooibos peaks in the summer months, implying a reliance on soil moisture. The current study aims to investigate the relationship between rooibos growth and soil moisture. The objectives of the study were: 1) to determine the effect of soil moisture on growth and evapotranspiration in rooibos under glasshouse conditions, 2) to adapt the CROPGRO model in DSSAT to simulate the shoot biomass yield of rooibos, using the rooibos CROPGRO model, 3) to investigate the effect of rooibos growth on soil moisture, and 4) to determine the effect of different levels of mulching and irrigation on rooibos yield and soil moisture. Some of the results obtained in the glasshouse study in Objective 1 and observational field data from the literature were used in the adaptation of the CROPGRO model. The glasshouse study was carried out at the University of Cape Town, using soils from Clanwilliam and Citrusdal sites to grow rooibos seedling for 16 weeks in pots before exposing them to drought treatments. The pots were arranged on trays in the glasshouse using a completely randomized design. Two drought treatments were used: moderate drought stress (MDS), set at 20% FC, and severe drought stress (SDS), during which watering was completely withdrawn, were applied to 10 pots per treatment per site. Data on plant growth, root morphology, evapotranspiration, soil moisture, chlorophyll fluorescence and leaves to determine chlorophyll and carotenoid concentration were collected from the plants in the glasshouse after 10 days of these drought treatments. The SDS plants were re-watered for 8 weeks for recovery, and together with the MDS and control plants were transferred into a growth chamber for measurement of gas exchange parameters and biomass. The CROPGRO model in DSSAT was adapted for rooibos by changing some parameters in a pigeon pea (Cajanus cajan L. Millspaugh) CROPGRO model. The adapted rooibos model was used to set up an experiment that compared the cumulative evapotranspiration and soil moisture from the rooibos field and bare soil under rainfed conditions. Also, in a simulation experiments, the model was used to determine the effect of three levels of mulching by means of wheat residue at 8000 kg/ha, 4000 kg/ ha and 2000 kg/ha and drip irrigation at 25.4mm and at 12.5mm once a week from December to March, both separately and in combination, on rooibos shoot biomass and soil moisture. The results from the glasshouse study showed a 40% decrease in biomass under MDS conditions for 12 weeks, while SDS plants could not survive beyond 10 days in the glasshouse. Root morphological features changed under severe drought stress, resulting in longer and thinner roots relative to the control plants. The reduced biomass accumulation under drought conditions was followed by reduced photosynthesis, stomata conductance, transpiration, and concentration of chlorophyll and carotenoids. Changes in both maximum quantum efficiency of photosystem II (Fv/Fm) and fluorescence quantum yield (Fq'/Fm') were observed in the later stages of the SDS plants (days 9 and 10) compared to the control plants but were unaltered in the MDS plants. The soil moisture correlated negatively with evapotranspiration and stomata conductance in control plants, while these relationships were absent in MDS plants. Changes in temperature in the glasshouse correlated positively with stomata conductance and transpiration in the control plants, but these correlations were also absent in MDS plants. However, changes in temperature correlated negatively with soil moisture in both the control plants and the MDS treated plants. The CROPGRO model in DSSAT was successfully adapted to simulate shoot biomass in rooibos under field conditions and the rooibos model had an agreement of 94% with observational shoot biomass under field conditions. Furthermore, the model simulated cumulative evapotranspiration in rooibos plants in the field, with an agreement of 56%. The simulated experiments showed that cumulative evapotranspiration from the rooibos field was 33% higher than that of bare soil, and showed that rooibos plants extract moisture from deep soil layers to a depth of about 2 m. Furthermore, rooibos growth in deep soil, and in mulched or irrigated treatments, produced higher shoot biomass than control plants. In deep soil, the simulated irrigated rooibos plants, which received 25.4 mm water weekly from December to March, produced a higher biomass yield than only rainfed or mulched plants. However, the combined treatments of mulching at 8000 or 4000 kg/ha and irrigation at 12.5 mm was similar to irrigation at 25.4mm. The average extractable soil moisture was greater in deep soil for all the treatments and control plants compared to shallow soil. Overall, the rooibos crop model shows that an increased supply of soil moisture enhances the production of biomass yield in rooibos in the field. Also, rooibos extracts moisture from a deeper soil layer, which enables it to hydrate its leaves and to transpire during the summer period for better growth and biomass production. Water loss through evapotranspiration was high in rooibos fields, and thus mulching of the plants would be beneficial for increased biomass production. However, even better rooibos yields were obtained when mulching was combined with irrigation. The glasshouse experiments showed a yield decrease of rooibos biomass by about 40% when the moisture supply was reduced by about 50% of the adequate conditions. The thinner and longer roots of rooibos, among other drought tolerance traits, most likely enable it to cope with low rainfall and drought conditions, which are prevalent in the Cederberg region of the Western Cape. The production of rooibos in the farms is prone to water loss through evapotranspiration, and thus soil moisture conservation technologies such as mulching would greatly enhance its biomass yield
Antidiabetic properties of centella asiatica in type II diabetic rats.
Get PDFDoctor of Philosophy in Biochemistry. University of KwaZulu-Natal, Durban 2016.Abstract available in PDF file
A first principles computational study of ZnO/PbTiO₃ as a tunable catalyst for CO₂ conversion
No full textThesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.Thesis: S.M., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2015.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 119-126).Due to its role in climate change, there is great interest in finding ways to take advantage of the vast amount of waste CO₂ we produce by its conversion to useful substances. This approach is currently impractical due to the high temperatures and pressures generally required for the synthesis of compounds using CO₂ as a precursor. To make direct CO₂ capture and conversion economically viable, new materials able to catalyze the conversion reactions at significantly milder conditions will be essential. In this thesis, we use DFT computations to begin the design of a dynamically tunable ferroelectric oxide-supported thin film catalyst that can capture CO₂ directly from the emission stream and convert it into methanol or cyclic carbonates. Promising candidates for a dynamically tunable catalyst of this type are the different combinations of ZnO directions grown on the perovskite PbTiO₃. For the non-polar ZnO(112̄0) grown on the perovskite, we demonstrate that the surface chemistry is dependent on both the polarization direction of the PbTiO₃ substrate and on the number of ZnO(112̄0) layers n. Growing the ZnO in the (0001) direction on the perovskite showed even more interesting results. We found that this process is sufficient to obtain a ZnO ferroelectric and is superior to previous attempts to make ferroelectric phase changes possible in the oxide, namely Li-doping. We demonstrate that switching the polarization direction of the perovskite substrate is sufficient to switch the polarity at the ZnO surface. This is an excellent basis for a dynamically tunable catalyst.by Babatunde Alawode.S.M
Effects of computerized and non-computerized stress reduction program on stress levels of Black African male and female students at Atlanta Metropolitan College: implications for counseling, 1990
No full textThis study was designed to compare the effects of two stress reduction programs on selected male and female Black African students, enrolled in a public two-year liberal arts college in Atlanta, Georgia. An additional purpose was to determine if significant differences existed between selected male and female Black African students in their stress levels. The participants consisted of 15 male and 18 female Black African students. The instrument used in this study for data collection was the Coping Resource Inventory (CRI). The research design for this study was quasi experimental, t-test and two-way Anova procedures were used to analyze the data. The results of the t-test at the .05 level of confidence showed significant difference between pre-and-post test results for the computerized stress reduction program
NMR LABORATORY Introduction with a Time Lapse and Tilt-shift Video
Get PDFOulu University of Applied Sciences
Degree Programme in Information Technology
Author: Adebowale Babatunde Adejuwon
Title of Bachelor’s thesis: NMR- Laboratory, introduction with a Time Lapse and Tilt-shift video.
Supervisor: Juha Räty
Term and year of completion: Spring 2012 Number of pages: 38
This thesis was based on a very demanding video project for University of Oulu Physic Laboratory NMR group. The objective of the thesis was to make a video to introduce the NMR group in the Physics department at the University of Oulu to young and prospective students. This video editing project was not just about editing, I had to study a lot of very new and demanding programmes that combine video, time lapse and tilt-shift techniques as the aim was to produce a Multimedia style of an interesting video for YouTube and other sources in order to make this NMR laboratory look interesting among young people.
The main video editing tools used in this thesis were Adobe Premiere Pro CS5 for a Windows 64-bit operating system and Adobe After Effects to make time lapse and tilt-shift. Also used was Goldwave which is a digital audio editing software with advanced audio restoration effects and processing tools.
I also learnt how to record videos and deal with robot cameras. The whole process was not just about editing, because it involved writing what happens in the film, some programming, handling both video cameras and time lapse cam-eras, combining audio and video tracks, learning how to take away noises (sur-rounds) from audio tracks, choosing the format suitable for the Internet, a DVD, or whatever sources needed here in the NMR laboratory.
As a result, I made a video about these video effects in DVD and Internet forms for NMR laboratory.Oulun seudun ammattikorkeakoulu
Tietotekniikan koulutusohjelma
Tekijä: Adebowale Babatunde Adejuwon
Opinnäytetyön nimi: NMR-laboratorio, esittely timelapse- ja tilt-shift-tekniikoilla
Työn ohjaaja: Juha Räty
Työn valmistumislukukausi ja -vuosi: Kevät 2012 Sivumäärä: 38
Tämä opinnäytetyö perustuu vaativaan Oulun yliopiston fysiikan laitoksen NMR-laboratorion videoprojektiin. Opinnäytetyön tavoite on luoda esittelyvideo NMR-tutkimuksesta Oulun yliopiston fysiikan laitoksen nuorille ja lupaaville opiskelijoille. Saadaksemme NMR-laboratoriosta kiinnostavan nuorille, tämä videoprojekti ei ollut vain videon editointia. Siihen liittyi uusien ja vaikeiden muokkausohjelmien hallinta yhdistämällä video-, timelapse- ja tilt-shift-liiketekniikoita multimediavideon tuottamiseksi nuorille sopiviin formaatteihin, mm. Youtube-palveluun.
Pääeditointiohjelmina tässä projektissa käytettiin Adobe Premiere Pro CS5 -ohjelmistoa 64-bittiselle Windowsin käyttöjärjestelmälle sekä timelapse- ja tilt-shift-tekniikan toteutukseen Adobe After Effects -ohjelmaa. Lisäksi käytimme Goldwave-nimistä ohjelmaa. Goldwave on digitaalisen äänen muokkausohjelma, josta löytyy edistyneitä äänenkorjaus- ja käsittelytyökaluja.
Työssä perehdyttiin myös videoiden taltiointiin ja robottikameran käyttöön. Projekti ei ole vain videon muokkaamista, koska siihen liittyy myös muistiinpanojen ottamista filmistä, ohjelmointia kuinka hallita videokameraa ja aikavälikameraa yhtäaikaisesti, video- ja ääniraitojen liittämistä, melun erottelemista ääniraidoista ja videon saattamista valmiiksi DVD-, Internet- ja NMR-laboratoriossa tarvittaviin formaatteihin.
Lopputuloksena saatiin paljon videoita DVD:n ja nettivideoiden muodossa NMR-laboratorion käyttöön.
Asiasanat
NMR-laboratorio, Adobe Premiere CS5, videoeditointi, tilt-shift-tekniikka, timelaps
The Dynamics of Spatial Structure and Spatial Pattern Changes at the Fringe Area of Makassar City
Get PDFThe study is conducted at the fringe area of Makassar City by analyzing dynamics of spatial structure and spatial pattern changes at the fringe area of Makassar City. It applies quantitative and qualitative approaches (mixed method). Data is acquired from some sources and informants living at the fringe area of Makassar City. Spatial utilization shift and development of transport infrastructure, especially for main road corridor connecting down town of Makassar City and fringe area, affect significantly spatial structure and spatial pattern changes at the fringe area of Makassar City. Dynamics of spatial structure and spatial pattern changes contributes changes of resident mobility; while, development tendency of the existing spatial and land use is no longer determined based on productivity, but it is valued by functions of space and land at the fringe are of Makassar City
Relationship among Sports Participation, Self-Perception and Gender Role Orientation of Adolescent Female Students in Kwara State, Nigeria
No full textThis study examined the relationship among sports participation, self-perception and gender role orientation of adolescent female students in Kwara State. Descriptive survey design was adopted for the study. 240 respondents were sampled from public secondary schools in Kwara State through simple random sampling technique; eight (8) public secondary schools were selected. Stratified and proportionate sampling techniques were used to select 20% of students by class. The research instrument was a self-structured close ended questionnaire. The data collection was conducted by the researcher and three (3) research assistants. Three null hypotheses were tested using Pearson’s Product Moment Correlation (PPMC) statistic at 0.05 alpha level. The findings revealed no significant relationship between self-perception and sports participation, there was significant relationship between gender role orientation and sports participation. Also, there was significant relationship between social interaction and sports participation among the adolescent female students. The study recommends that the concept of sports should be promoted among the students while female students should be given equal opportunity in sports as their male counterpart. Also all students should be encouraged to participate in sports in order to promote social relationship with other students
Telecommunication (GSM) and Urban Spatial Structure in Ibadan North Local Governmnet Area, Nigeria
No full textAbstract: The role and impact of novel telephone technology in shaping urban structure has produced two schools of thought. The first is evolutionary, which believe in the continuing primary of physical movements and the second, is revolutionary which elevates the importance of non-physical information flows. The revolutionaries believes that new telecommunication innovations will create a flexible electronic environment that will enable people to inhabit attractive amenity environments, remote from declining urban centers thereby influencing people's choice as regards location in urban setting. In this study an analysis of the effect of mobile communication through the use of GSM phone on intra-urban movements and location decision was considered. Study revealed that mobile communication does not have much effect on important trips such as trips to work, to market place, shopping centers and recreational locations. It is concluded that most of the trips eliminated through the use of mobile phone are discretionary trips. The study also discovered that income rather than communication largely determines the location of households in Ibadan North. It is therefore concluded that communication has not inverted the existing spatial pattern since it has not withdrawn trip away from important centers or changed the location pattern of activities in the study area
NEED FOR COMPLIANCE TO HEALTH AND ECONOMIC SUSTAINABLE DEVELOPMENT STANDARDS IN OIL EXPLORATION AREAS OF ONDO STATE
No full textreservedThe recent updated on the oil producing area of Ondo state has prompted considerable research. This study aims to investigate the need to implement a functioning health and economic sustainable development scheme in the oil producing areas of Ondo state. Therefore, an assessment of the level of compliance of oil exploration companies within the oil producing areas of Ondo state to the standards of sustainability was done. The study identifies and present statistics of the current challenges posed to Ondo state oil producing host communities by the exploration and exploitation of oil. Also, the study also revealed the economic and health needs in host communities of oil exploration within Ondo state. A discovery of the political actions that can be taken by local community to achieve economic and health sustainable development standards. Furthermore, a chi-square test of independence was performed to examine the relationship between the location of respondents and respondents knowledge which the findings revealed that economic and health development projects in Ilaje local government area have not yet complied with the united nation sustainable development goal 1 and 3. The findings also prove the theory of economic, political and social distortion judging by the dissimilarities of the authorities. Geographic disparities theory was also used to ascertain the fact that environment can cause spatial poverty. The study recommends the collaboration of the oil companies, government and the indigenous people of the host communities to further promote sustainability in the area.The recent updated on the oil producing area of Ondo state has prompted considerable research. This study aims to investigate the need to implement a functioning health and economic sustainable development scheme in the oil producing areas of Ondo state. Therefore, an assessment of the level of compliance of oil exploration companies within the oil producing areas of Ondo state to the standards of sustainability was done. The study identifies and present statistics of the current challenges posed to Ondo state oil producing host communities by the exploration and exploitation of oil. Also, the study also revealed the economic and health needs in host communities of oil exploration within Ondo state. A discovery of the political actions that can be taken by local community to achieve economic and health sustainable development standards. Furthermore, a chi-square test of independence was performed to examine the relationship between the location of respondents and respondents knowledge which the findings revealed that economic and health development projects in Ilaje local government area have not yet complied with the united nation sustainable development goal 1 and 3. The findings also prove the theory of economic, political and social distortion judging by the dissimilarities of the authorities. Geographic disparities theory was also used to ascertain the fact that environment can cause spatial poverty. The study recommends the collaboration of the oil companies, government and the indigenous people of the host communities to further promote sustainability in the area
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