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The relationship between firm size and exports in the context of merger review in South Africa : is the international competitiveness public interest clause of the Competition Act validAproskie, Jason January 2005 (has links)
Includes bibliographical references (leaves 32-34). / According to the Competition Act of South Africa, proposed mergers, if rejected on the grounds of anti-competitive effects as well as the efficiency considerations, may be passed on certain public interest grounds. The fourth public interest clause potentially allows mergers to be passed should the merged firm become more able to compete in international markets. This paper interprets the clause to refer to a relationship between firm size and exports, and investigates this supposed relationship and, in so doing, the validity of the clause. It is found that firm size is positively related to export propensity, the likelihood of exporting any output. However, firm size is found to be unrelated to the intensity of exporting, the proportion of output that is exported by the firm. This paper covers new areas of research, and its conclusions call into question the inclusion of the relevant public interest clause in the Competition Act.
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Influence of Sediment Composition on Apparent Toxicity in a Solid‐phase Test Using Bioluminescent BacteriaBenton, Michael J., Malott, Michelle L., Knight, Scott S., Cooper, Charles M., Benson, William H. 01 January 1995 (has links)
Clean and spiked sediment formulations of various silt sand and clay sand ratios were tested for toxicity using a bioassay that utilizes bioluminescent bacteria Measured toxicities of clean and copper sulfate–spiked sediments were negatively but nonlinearly related with percent silt and percent clay, but no significant relationship existed between measured toxicity and sediment composition for methyl parathion–spiked formulations Results suggest that solid phase sediment bioassays using bioluminescent bacteria may be useful for testing the toxicities of single contaminants in formulated artificial sediments of known particle size composition, and for repeated samples collected from the same site However, extreme caution must be taken when testing sediments of varying composition or which may be differentially contaminated or contain a suite of contaminants.
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Regional Constraints on Leaf Physiognomy and Precipitation Regression Models: A Case Study From ChinaSu, Tao, Spicer, Robert A., Liu, Yu Sheng Christopher, Huang, Yong Jiang, Xing, Yao Wu, Jacques, Frédéric M.B., Chen, Wen Yun, Zhou, Zhe Kun 09 July 2013 (has links)
The relationship between leaf physiognomy and precipitation has been explored worldwide in regions under different climate conditions. Unlike the linear relationship established between the percentage of woody dicot species with entire margins and mean annual temperature, precipitation has been reported to correlate to different leaf physiognomic characters depending on the region where the correlation is studied. To investigate if precipitation can be calculated from leaf physiognomic characters on the basis of regional sample sites, data from 50 mesic to humid forests in China were analyzed in this study. With data from Chinese forests, the leaf-area analysis based on linear regression between natural logarithms of leaf size and mean annual precipitation (MAP) shows no significant correlation. Both single and multiple linear regression analyses fail to confirm the correlation between leaf physiognomy and precipitation, which may result from the similarity of modern spatial distribution of temperature and precipitation in China. Our results show that, due to variations in climatic conditions among sampling regions, leaf physiognomic characters that correlate to precipitation are not consistent worldwide, and applications of models without considering regional constraints could mislead our understanding of palaeoclimate. Therefore, when choosing a leaf physiognomic model for palaeoclimate reconstructions, it is important to determine if the leaf physiognomy of the palaeoflora lies within the leaf physiognomic spectrum of the model used.
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Regional Constraints on Leaf Physiognomy and Precipitation Regression Models: A Case Study From ChinaSu, Tao, Spicer, Robert A., Liu, Yu Sheng Christopher, Huang, Yong Jiang, Xing, Yao Wu, Jacques, Frédéric M.B., Chen, Wen Yun, Zhou, Zhe Kun 09 July 2013 (has links)
The relationship between leaf physiognomy and precipitation has been explored worldwide in regions under different climate conditions. Unlike the linear relationship established between the percentage of woody dicot species with entire margins and mean annual temperature, precipitation has been reported to correlate to different leaf physiognomic characters depending on the region where the correlation is studied. To investigate if precipitation can be calculated from leaf physiognomic characters on the basis of regional sample sites, data from 50 mesic to humid forests in China were analyzed in this study. With data from Chinese forests, the leaf-area analysis based on linear regression between natural logarithms of leaf size and mean annual precipitation (MAP) shows no significant correlation. Both single and multiple linear regression analyses fail to confirm the correlation between leaf physiognomy and precipitation, which may result from the similarity of modern spatial distribution of temperature and precipitation in China. Our results show that, due to variations in climatic conditions among sampling regions, leaf physiognomic characters that correlate to precipitation are not consistent worldwide, and applications of models without considering regional constraints could mislead our understanding of palaeoclimate. Therefore, when choosing a leaf physiognomic model for palaeoclimate reconstructions, it is important to determine if the leaf physiognomy of the palaeoflora lies within the leaf physiognomic spectrum of the model used.
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Genome Sizes of Granes (Aves: Gruiformes)Rasch, Ellen 01 December 2006 (has links)
The DNA content of blood cell nuclei of 15 species of cranes was determined by Feulgen-DNA cytophotometry. Genome sizes agree with values reported elsewhere for several crane species analyzed by flow cytometry. Males have more DNA per cell than females in several species. A karyotype where 2n = 80 is reported for a male greater sandhill crane.
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DNA-Feulgen Cytophotometric Determination of Genome Size for the Freshwater-Invading Copepod Eurytemora AffinisRasch, Ellen M., Lee, Carol Eunmi, Wyngaard, Grace A. 01 June 2004 (has links)
Variation in nuclear DNA content within some eukaryotic species is well documented, but causes and consequences of such variation remain unclear. Here we report genome size of an estuarine and salt-marsh calanoid copepod, Eurytemora affinis, which has recently invaded inland freshwater habitats independently and repeatedly in North America, Europe, and Asia. Adults and embryos of E. affinis from the St. Lawrence River drainage were examined for somatic cell DNA content and the presence or absence of embryonic chromatin diminution, using Feulgen-DNA cytophotometry to determine a diploid or 2C genome size of 0.6-0.7 pg DNA/cell. The majority of somatic cell nuclei, however, have twice this DNA content (1.3 pg/nucleus) in all of the adults examined and possibly represent a population of cells arrested at the G2 stage of the cell cycle or associated with some degree of endopolyploidy. Both suggestions contradict assumptions that DNA replication does not occur in adult tissues during the determinate growth characteristic of copepods. Absence of germ cell nuclei with markedly elevated DNA values, commonly found for species of cyclopoid copepods that show chromatin diminution, indicates that E. affinis lacks this trait. The small genome size and presumed absence of chromatin diminution increase the potential utility of E. affinis as a model for genomic studies on mechanisms of adaptation during freshwater invasions.
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Characterising South Africa’s major dust sourcesBekiswa, Sisanda Ongeziwe 24 February 2020 (has links)
The study investigates the surface controls of major dust emissions and determines the patial distribution of major dust source in South Africa. This study follows a multi-disciplinary approach where primary and secondary data were used. The main objective of the study is to determine the spatial distribution of South Africa's Major Dust Sources. Meteosat Second Generation (MSG) satellite imagery, land use and land cover maps were used to achieve the first and the second objectives of the study. Primary data involved sampling 30 soil samples in the field in order to achieve the third objective of the study. The crust, soil moisture, soil texture and grain size are all controls of dust emission. This investigation is however focused predominantly on grain size characteristics. GIS methods were also used to determine soil type from the African soil map. Soil samples in both provinces were then collected to assess the Particle Size Distribution (PSD) of the soils. The particle size was determined based on a sieve analysis for grain sizes that were greater than 2mm and laser diffractometry, MasterSizer (Malvern) was used to achieve this. The results from the Malvern were later put to R Statistics where they were clustered into eight clusters to determine similarities and difference of the grain size. Because there is no uniqueness in the soil types found in the study area, there were no solid conclusions made based in them. The results show that the soil types are found across South Africa but not the same amount of dust activity was detected in the other parts of the country. Previous studies show that global significant dust sources are natural sources such as lakes, pans and depressions. However, results demonstrate that South African dust sources are anthropogenic sources resulting from commercial agriculture in semi-arid regions. This study has demonstrated that surface sediments suitable for dust production are a mixture of fine material, silt (50µm) and coarse material, sand (2000µm) and it appears that all clusters in this study all contained both mixtures and all have potential to emit dust.
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Ideal Size of Family Among Unmarried Females in Northern UtahJohnson, Ronald B. 01 May 1969 (has links)
Preferences of the size of family and the relationship between the size of family and a number of socio - economic and demographic variables were studied among high school senior girls in three northern Utah counties by a special survey.
The questionnaire specifically designed for the study was administered between November 1967 and February 1968 in all high schools in Cache, Box Elder and Rich counties with the exception of Logan High School in Logan and Box Elder High School in Brigham City.
Two questions were used to elicit the answers on the preference of family size; one was designed to elicit an answer with the respondent as the point of reference and the other was the "generalized other" as a reference point. Both sets of data were c ross-tabulated with socio - economic and demographic variables.
Both data indicated that the mean number of children desired was 4 .4 and 4.3 for the family of "generalized others " and the respondent's own family respectively.
A weak relationship was found between the ideal size of family and the education of respondent's mother and father, income, religion, residence, occupation, and the demographic variable, the respondent's own family size. The data also indicated that those with a belief in birth control prefer a smaller family than those who do not believe in the use of contraceptive devices.
Due to the sample size and the exploratory nature of the study, relationships between ideal size of family and the selected number of variables can only be suggestive.
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Measurement of the Cross-Sectional Area of the Nasal Passages of Nine Species of Modern Odontoceti with Implications for Comparative Physiology and the Paleophysiology of the DinosauriaKatz, Eric Paul 05 March 1999 (has links)
In search of evidence for or against the endothermic dinosaur hypothesis, a recent study by Ruben et al. (1996) revealed that endotherms tend to have larger nasal cross-sectional areas than ectotherms of the same mass. The reason offered for this observation was that larger nasal passages are needed to house the complex respiratory turbinates possessed by endotherms. Whales were excluded from the study on the grounds that they have no nasal turbinates. In the present study, the cross-sectional area of the nasal passages of nine species of Odontoceti were measured by the use of latex casts. The regression of log cross-sectional area vs. log mass yielded the same line for the whales of the current study as for the endotherms of the previous study. Alternative explanations for the large nasal cross-sectional area of endotherms are sought.
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Sample Size Determination in Multivariate Parameters With Applications to Nonuniform Subsampling in Big Data High Dimensional Linear RegressionWang, Yu 12 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Subsampling is an important method in the analysis of Big Data. Subsample size determination (SSSD) plays a crucial part in extracting information from data and in breaking the challenges resulted from huge data sizes. In this thesis, (1) Sample size determination (SSD) is investigated in multivariate parameters, and sample size formulas are obtained for multivariate normal distribution. (2) Sample size formulas are obtained based on concentration inequalities. (3) Improved bounds for McDiarmid’s inequalities are obtained. (4) The obtained results are applied to nonuniform subsampling in Big Data high dimensional linear regression. (5) Numerical studies are conducted.
The sample size formula in univariate normal distribution is a melody in elementary statistics. It appears that its generalization to multivariate normal (or more generally multivariate parameters) hasn’t been caught much attention to the best of our knowledge. In this thesis, we introduce a definition for SSD, and obtain explicit formulas for multivariate normal distribution, in gratifying analogy of the sample size formula in univariate normal.
Commonly used concentration inequalities provide exponential rates, and sample sizes based on these inequalities are often loose. Talagrand (1995) provided the missing factor to sharpen these inequalities. We obtained the numeric values of the constants in the missing factor and slightly improved his results. Furthermore, we provided the missing factor in McDiarmid’s inequality. These improved bounds are used to give shrunken sample sizes.
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