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Framgångsfaktorer för parprogrammering inom Extreme ProgrammingEskandari, Edvin January 2005 (has links)
Det här arbetet har med hjälp av en kvalitativ undersökning tagit fram framgångsfaktorer för parprogrammering. Detta har genomförts med hjälp av intervju samt enkätundersökningar med sex respondenter. Då litteraturen inte behandlar hur parprogrammering kan bli framgångsrikt har detta arbete haft som syfte för att göra detta. Resultatet har kategoriserats i fyra nivåer. Exempel på framtagna framgångsfaktorer är att: • ledningen måste införskaffa kunskaper om parprogrammering • projektledaren uppmuntrar till byte av par ofta • projektdeltagarna är öppna och mottagbara för konstruktiv kritik
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Development of a novel high throughput method for identifying phage-host pairs in an extreme environmentOlonade, Israel Temiloluwa January 2017 (has links)
Philosophiae Doctor - PhD / There are approximately 10³¹ bacteriophages in the biosphere, outnumbering bacteria 10:1, hence, the dynamic and specific nature of phage-host interactions exerts significant influence on microbial communities. Bacteriophages also represent the reservoir of the highest known genetic diversity making them a potential source of novel biotechnological products. However, the isolation of novel bacteriophages is limited by the observation that less than 1% of bacterial hosts have been cultured. This study aimed to bypass this problem by developing novel culture independent approaches to improve our ability to isolate novel phage-host pairs. Samples were collected from an abandoned copper prospecting site near the Gobabeb Desert Research and Training Station and a Salt lake located in the Swakopmund region of the Namibian desert. Two approaches were explored in this study namely viral tagging and reverse metaviromics. For viral tagging, fluorescently labelling the environmental phage fraction before challenging the environmental bacterial fraction with tagged phages proved difficult. This was most likely due to the complex interaction of the labelling agent with phages and requires further studies. For the reverse metaviromics approach, total DNA from the environmental phage fractions was extracted, sequenced and analyzed for novel phages. Analysis of the phage diversity showed that the copper site was dominated by tailed viruses as has been shown for other extreme arid environments. However, the saline site was atypical of marine environments, with tailed viruses being the most abundant, suggesting that the diversity present is not only driven by salinity. Using the metaviromic sequence data to guide the selection of potential bacterial hosts, two strategies were employed. In the first, putative hosts were predicted based on similarity of phage sequences to those identified in databases. Media targeting these specific genera were employed, 8 bacterial species were isolated and based on 16S rRNA similarity to the closest known species were identified as Halomonas caseinilytica, Halomonas eurihalina, Halomonas sinaiensis, Idiomarina loihiensis, Marinobacter xestospongiae, Virgibacillus salarius and two Salinivibrio species. The 16S rRNA analysis also suggested that H. sinaiensis, V. salarius and both Salinivibrio species are novel. All 8 isolates were challenged with the environmental phage fraction. A novel phage, SMHB1, was isolated on one of the Salinivibrio spp. and is only the second characterized phage ever described for this genus. SMHB1 is a 32 kb myovirus, with a head diameter of 56 nm, and a tail length of 106 nm. The second approach involved the design of fluorescently labelled probes targeting phages identified from the metaviromic sequence data. In a control E. coli system to detect cloned phage DNA fragments, 87% of the interrogated cells showed significant hybridization of the phage specific probe to the target. The optimized method was applied to a simulated environmental bacterial fraction and a detection limit of 1:100 was observed for the bacteria containing the phage DNA fragment of interest. This study demonstrates the possibility of improving the specificity of isolating phage-host pairs in a culture-independent manner by incorporating sequence data in the experimental design; and contributes to our knowledge of the phage diversity of an understudied extreme environment.
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Fitting extreme value distributions to the Zambezi river flood water levels recorded at Katima Mulilo in NamibiaKamwi, Innocent Silibelo January 2005 (has links)
Magister Scientiae - MSc / The aim of this research project was to estimate parameters for the distribution of annual maximum flood levels for the Zambezi River at Katima Mulilo. The estimation of parameters was done by using the maximum likelihood method. The study aimed to explore data of the Zambezi's annual maximum flood heights at Katima Mulilo by means of fitting the Gumbel, Weibull and the generalized extreme value distributions and evaluated their goodness of fit. / South Africa
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Actinobacterial and archaeal diversity in lake Magadi, KenyaHalimat, Olubukola Ibrahim January 2013 (has links)
>Magister Scientiae - MSc / Microorganisms of the class Actinobacteria and domain Archaea are interesting from a
biotechnological perspective owing to their metabolic attributes as producers of
secondary metabolites and resilience under harsh environmental conditions respectively.
Lake Magadi is a soda lake well studied in terms of its geology and limnology. Research
attention has also been drawn to the microbial populations which thrive in this unique
habitat but currently there are no reports on the assessment of its microflora using
molecular methods.
This study aimed to assess the actinobacterial and archaeal communities within Lake
Magadi, Kenya a hypersaline –highly alkaline habitat using metagenomic methods as a
preliminary study to identify potential candidates for exploitative biology
Samples from two sites dubbed Lake Magadi station 2 (LM2) and Lake Magadi salt pan
4 (LMS4) within the Lake Magadi were analyzed using the 16S rRNA gene as a
phylogenetic marker.
Cluster analysis of taxon-specific 16S rDNA PCR-DGGE profiles revealed moderately
heterogeneous actinobacterial and archaeal populations across the sample sites under
investigation which is probably a reflection of the differences in abiotic conditions at the
study sites. This observation was also confirmed from the multi-dimensional scaling
(MDS) plot.
PCR-based clonal libraries of actinobacterial and archaeal communities of both study
sites retrieved a total of thirty-two clones (twenty actinobacterial and twelve archaeal)
were sequenced. Analysis of the sequences revealed cultured and uncultured signatures of
microorganisms typical of hypersaline and or highly alkaline niches. A few (3) sequences
presented novelty (<96%) in identities with any previously identified organism. It was
concluded that the species dominance at site LMS4 [situated within the salt flats of Lake Magadi and site for exploration of trona and its mineralized extensions (nacholite and
gayllusite)] is likely to be dictated by anthropogenic stress since most of the microbial
signals associated with the study site are typical of saline and or alkaline environmental
samples exposed to especially mining but also agricultural and waste management
practices.
Isolation studies also revealed previously identified strains peculiar to hypersaline brines
and sediments. The strains retrieved were affiliated to the taxonomically diverse genus
Bacillus and Halomonas sp. The true applications and potential opportunities these
isolates have for biotechnology have been well documented.
Observations made from the culture dependent and culture independent methods suggests
strongly that study site LMS4 is subjected to environmental conditions more severe than
at site LM2.
This study is a guide for future studies as it provides primary information on the
haloalkaliphilic representatives of the actinobacteria phylum and domain Archaea within
the soda lake environment. It can serve as a pedestal for investigation into the molecular
machinery that supports the haloalkaliphilic lifestyles of inhabiting microorganisms and
consequently give leads as to how they can be commercially exploited.
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Hurricane Loss Modeling and Extreme Quantile EstimationYang, Fan 26 January 2012 (has links)
This thesis reviewed various heavy tailed distributions and Extreme Value Theory (EVT) to estimate the catastrophic losses simulated from Florida Public Hurricane Loss Projection Model (FPHLPM). We have compared risk measures such as Probable Maximum Loss (PML) and Tail Value at Risk (TVaR) of the selected distributions with empirical estimation to capture the characteristics of the loss data as well as its tail distribution. Generalized Pareto Distribution (GPD) is the main focus for modeling the tail losses in this application. We found that the hurricane loss data generated from FPHLPM were consistent with historical losses and were not as heavy as expected. The tail of the stochastic annual maximum losses can be explained by an exponential distribution.
This thesis also touched on the philosophical implication of small probability, high impact events such as Black Swan and discussed the limitations of quantifying catastrophic losses for future inference using statistical methods.
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Extreme Value Theory with an Application to Bank Failures through ContagionNikzad, Rashid January 2011 (has links)
This study attempts to quantify the shocks to a banking network and analyze the transfer of shocks through the network. We consider two sources of shocks: external shocks due to market and macroeconomic factors which impact the entire banking system, and idiosyncratic shocks due to failure of a single bank. The external shocks will be estimated by using two methods: (i) non-parametric simulation of the time series of shocks that occurred to the banking system in the past, and (ii) using the extreme value theory (EVT) to model the tail part of the shocks. The external shocks we considered in this study are due to exchange rate and treasury bill rate volatility. Also, an ARMA/GARCH model is used to extract iid residuals for this purpose. In the next step, the probability of the failure of banks in the system is studied by using Monte Carlo simulation. We calibrate the model such that the network resembles the Canadian banking system.
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Development of Climate Change Scenarios for the South Nation WatershedAbdullah, Alodah January 2015 (has links)
Climate change studies are crucial to assist decision-makers in understanding future risks and planning adequate adaptation measures. In general, Global/Regional Climate Models (GCMs/RCMs) achieve coarse resolutions, and are thus unable to provide sufficient information to conduct local climate assessments. Downscaling, defined as a method that derives local to regional-scale (10 to 100 km) information from larger-scale models or data analyses, is used to address this deficiency. In this thesis, a particular downscaling technique, known as the Quantile-Quantile transformation, was used to adjust the statistical distribution of RCM variables to match the statistical distribution of the observed variables generated by two RCMs: the Canadian Regional Climate Model version 3.7.1 and the ARPEGE model, on the historical period (1961-2001). The analyses presented in this study were applied to daily precipitation and maximum and minimum temperatures in the South Nation watershed in Eastern Ontario, Canada. The two-sample Kolmogorov–Smirnov test indicated that the Quantile-Quantile transformation improved the shape of the PDF of RCM-simulated climate variables. The results suggest that, under the A1B scenario, temperatures in the watershed would rise significantly and there would be an increment in precipitation occurrence and intensity. Trend analysis was performed on the 1961 to 2001 and 2041 to 2081 timeframes, using the Mann-Kendall test and the Sen's slope estimator. Discernible, often significant, increases of maximum and minimum temperatures were found for the 1961 to 2001 period, and stronger ascending slopes for the 2041 to 2081 period. However, there was marginal evidence of changes in the time series of maximum and accumulated annual precipitation for both periods. The study also outlined how the frequency and intensity of some extreme weather events will evolve in the 2041-2081 period in response to the rise in atmospheric GHG concentrations. Projected impacts were investigated by tracking future changes in four extreme temperature indices and three precipitation indices. It was predicted that heavy precipitation events and warm spells will occur more frequently and intensely, while extreme cold events will be weaker, and some will be hardly observed.
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Risk, blame, and expertise : the Meteorological Office and extreme weather in post-war BritainHall, Alexander January 2012 (has links)
This thesis explores the post-war history of the British Meteorological Office (MO), which saw the development of public weather services and a more prominent profile for the organisation in British public life. Situated within a post-war growth in the scientific civil service and the government’s use of science in policy making, the emergence of MO extreme weather warnings and forecasts afforded the organisation an authoritative expert position. Part of meteorology’s twentieth century professionalisation, the services developed through the application of advances in meteorological practice and technologies, significantly altered the organisation’s public profile and status as a scientific expert body.By considering these developments the thesis illuminates how, as the MO increasingly presented forecasts and warnings to all sectors of British society, they became managers of the risks posed by extreme weather. Through exploring these historical developments at the MO, we see a broader narrative emerge on how the communication of risk by scientific experts interacts with public expectations and manifestations of blame. Central to the narrative presented is the role of extreme weather events themselves in affecting response, policy developments, new MO warning services, and the manifestation of blame.
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Iniciativa D.O.S.T. jako radikálně konzervativní výzva současnosti / Initiative D.O.S.T. as a radically conservative challenge of presentKříhová, Dominika January 2011 (has links)
This thesis focuses on the analysis of initiative D.O.S.T., currently one of the most important Czech extreme-right groups. D.O.S.T. comes with a radically conservative critique of current concepts and direction of democracy, yet she managed to reach support among political parties accepted as legitimate and also influential public figures. The work is based on the assumption, that the main reason for this is that the initiative despite being extremely right-wing organization, highlights also real deficits of democracy. Therefore it can be seen as a challenge of present. The aim of this paper is to analyze critically this challenge by mentionning the initiative in all relevant contexts. The paper therefore deals firstly with the intellectual and political roots of its founders in the extreme right-organization called Právo a Spravedlnost. After it analyzes the initiative itself, its manifesto, activities, the main problematised issues and linkages with other political forces. In conclusion, the papers considers the perspective of eventual genesis of a new political party established by the initiative D.O.S.T.
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Evolutionary timescales of AO-produced speckles at NIR wavelengthsGoebel, Sean B., Guyon, Olivier, Hall, Donald N. B., Jovanovic, Nemanja, Atkinson, Dani E. 26 July 2016 (has links)
We present measurements of the evolutionary timescales of speckles around adaptive optics-corrected PSFs. We placed a SELEX SAPHIRA HgCdTe detector behind the SCExA0 instrument at Subaru Telescope. We analyzed the behavior of speckles at radial distances of 2-8 A/D away from the diffraction-limited PSF in H-band (-1.6 m) images collected at 1 kHz framerates. Speckles evolve with a variety of timescales, and these have not previously been studied at near-infrared wavelengths. Ultimately we would like to image reflected-light exoplanets, which necessitates a fast speckle control loop. Based on our measurements, we calculate the parameters of an optimized control loop that would enable such observations.
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