879 resultados para ten Haven, Paul: Doing conversastion analysis.


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Detailed organic geochemical investigations have been performed on sediment samples from upwelling Site 658 and nonupwelling Sites 657 and 659. The major objective of this study has been the relationship between organic carbon accumulation and paleoclimatic and paleoceanographic conditions in the upwelling area off northwest Africa during late Cenozoic times. The study is based on results from organic carbon, nitrogen, and hydrogen analyses, Rock-Eval pyrolysis, kerogen microscopy, gas chromatography, and gas chromatography/mass spectrometry. In general, nonupwelling Sites 657 and 659 are characterized by low organic carbon values of less than 0.5%. At Site 657, four events of high organic carbon deposition (total organic carbon of 1%-3%) occur and represent turbidites and a slump interval. The upper Pliocene to Pleistocene sediments of upwelling Site 658 display high organic carbon contents of 0.5%-4%, with higher contents concentrated in the upper Pliocene. Accumulation rates of organic carbon vary between 0.1 and 0.5 gC/cm-**2/1000 yr, with maximum values between 3.5 and 3.1 Ma. Short-term cyclic ("Milankovitch-type") variations in organic carbon accumulation suggest climate-controlled mechanisms causing these fluctuations. The quality of organic matter at Site 658 is a mixture of kerogen type II and HI, with a dominance of the marine type. This is indicated by high hydrogen-index values of 200-400 mgHC/gC, low C/N ratios of 5-15, atomic H/C ratios of 1.0-1.5, and high amounts of marine macerals (alginite and liptodetrinite). We have estimated paleoproductivity for Sites 658 and 659 based on the amount of marine organic carbon. At open-marine Site 659, mean paleoproductivity varies between 20 and 50 gC/m**2/yr. At Site 658, mean paleoproductivity reaches high values of 160 to 320 gC/m**2/yr, very similar to those recorded in modern upwelling areas. The changes in productivity off northwest Africa are linked to changes in nutrient supply caused by both upwelling and fluvial input. The change from a dominantly humid climate to one characterized by fluctuations between humid and fully arid climates in northwest Africa occurs between 3.1 and 2.45 Ma.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A number of C25 and C30 highly branched isoprenoid (HBI) sulphur compounds (E.G., thiolanes, 1-oxo-thiolanes, thiophenes, and benzo[b]thiophenes) with 2,6,10,14-tetramethyl-7-(3-methylpentyl)pentadecane and 2,6,10,14,18-pentamethyl-7-(3-methylpentyl)nonadecane carbon skeletons were identified in sediments, ranging from Holocene to Upper Cretaceous. These identifications are based on mass spectral characterisation, desulphurisation, and, in some cases, by comparison of mass spectral and relative retention time data with those of authentic standards. The presence of unsaturated C25 and C30 HBI thiolanes in a Recent sediment from the Black Sea (age 3-6 ka) strongly supports their formation during early diagenesis. The co-occurrence of HBI polyenes (C25 and C30) and unsaturated HBI thiolanes (C25 and C30) possessing two double bonds less than the corresponding HBI polyenes, in this Recent sediment, testifies to the formation of unsaturated HBI thiolanes by a reaction of inorganic sulphur species with double bonds of the HBI polyenes. Furthermore, a diagenetic scheme for HBI sulphur compounds is proposed based on the identification of HBI sulphur compounds in sediment samples with different maturity levels.

Relevância:

100.00% 100.00%

Publicador:

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper explores alterations in social dynamics caused by coca crops in Curvaradó and Jiguamiandó, at Choco department in the Colombian Pacific region. The research analyzes the role of armed actors such as paramilitaries and guerrillas in the conformation of new social spaces where local people find resistance as the main tool to survive in chaotic environments. Local power as a politics of resistance is also analyzed. Non-governmental organizations are a key tool to comprehend new social configurations. By doing the analysis and comparison using political ecology as the theoretical background along with concepts of moral economy and everyday resistance, with qualitative research methods. The paper aims to interpret and provide a better understanding of those changes considering social-environmental relations. Findings suggest that those changes in social structure are leading to an understanding, not just of the organization of the area, but also that social dynamics and coca crops cannot be generalized in the country. 

Relevância:

100.00% 100.00%

Publicador:

Resumo:

AIDS education is mandated in schools throughout the United States to educate students about the disease. Teachers are expected to assume the major role of disseminating this information; therefore it is reasonable to question how knowledgeable teachers are about HIV/AIDS and where their information is coming from. This study explored the knowledge and attitudes of general and special education teachers toward students with HIV/AIDS and investigated whether a relationship between knowledge and attitudes existed. Information was collected using the AIDS Knowledge and Attitude Survey (AKAS). The sample was limited to certified teachers resulting in 318 participants.^ Research questions were analyzed using descriptive statistics, frequencies, t-tests, one-way analysis of variance (ANOVA), Scheffe post hoc analysis, and Pearson Product-Moment Correlation. Results indicated that general and special education teachers did not have complete knowledge about HIV/AIDS. Participants were knowledgeable regarding modes of transmission which may be the area of greatest concern for teachers, however, deficiencies were present within teachers' knowledge of general statements and facts and pathology. Among the ten demographic variables analyzed, six (gender, race/ethnicity, level of education, certification, instructional level taught, and classroom AIDS instruction) contained statistical significance.^ Analysis of attitudes indicated that general and special education teachers' overall attitudes toward students with HIV/AIDS were generally positive within clusters of Instruction and Fear, but not within Sensitivity and Communication. Among the ten demographic variables used for analysis only three (age, graduate enrollment status, and classroom AIDS instruction) produced statistical significance. Results found statistically significant relationships between Total Knowledge, all knowledge subtests, Fear, and Overall Attitudes. Statistical significance was also located on Total Knowledge, Pathology and Transmission knowledge subtests, and Sensitivity, as well as between Pathology and Instruction, and General Statements and Facts and Communication.^ The only variable determined to have statistical significance on both knowledge and attitudes was classroom AIDS instruction. Participants with previous AIDS instruction showed greater knowledge and possessed more positive attitudes. A review of previous research indicated training to be effective in increasing knowledge and fostering more favorable behavior toward persons with AIDS. Therefore, this study finds AIDS training to be beneficial for all teachers and is recommended during preservice education or through inservices for teachers already in the field. ^

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Menu analysis is the gathering and processing of key pieces of information to make it more manageable and understand- able. Ultimately, menu analysis allows managers to make more informed decisions about prices, costs, and items to be included on a menu. The author discusses If labor as well as food casts need to be included in menu analysis and if managers need to categorize menu items differently when doing menu analysis based on customer eating patterns.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Few valid and reliable placement procedures are available to assess the English language proficiency of adults who enroll in English for Speakers of Other Languages (ESOL) programs. Whereas placement material exists for children and university ESOL students, the needs of students in adult community education programs have not been adequately addressed. Furthermore, the research suggests that a number of variables, such as, native language, age, prior schooling, length of residence, and employment are related to second language acquisition. Numerous studies contribute to our understanding of the relationship of these factors to second language acquisition of Spanish-speaking students. Again, there is a void in the research investigating the factors affecting second language acquisition and consequently, appropriate placement of Haitian Creole-speaking students. This study compared a standardized instrument, the NYS Place Test, used alone and in combination with a writing sample in English, to subjective judgement of a department coordinator for initial placement of Haitian adult ESOL students in a community education program. The study also investigated whether or not consideration of student profile data improved the accuracy of the test. Finally, the study sought to determine if a relationship existed between student profile data and those who withdrew from the program or did not enter a class after registering. Analysis of the data by crosstabulation and chi-square revealed that the standardized NYS Place Test was at least as accurate as subjective department coordinator placement and that one procedure could be substituted for li other. Although the writing sample in English improved accuracy of placement by the NYS test, the results were not significant. Of the profile variables, only length of residence was found to be significantly related to accuracy of placement using the NYS Place Test. The number of incorrect placements was higher for those students who lived in the host country from twenty-five to one hundred ten months. A post hoc analysis of NYS test scores according to level showed that those learners who placed in level three also had a significantly higher incidence of incorrect placements. No significant relationship was observed between the profile variables and those who withdrew from the program or registered but did not enter a class.