993 resultados para Ohio State Archaeological and Historical Society


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Book review of: Mark F. Chingono. The State, Violence and Development. The Political Economy of War in Mozambique, 1975–1992. Avebury (Aldershot, Brookfield USA, Hong Kong, Singapore, Sydney), 1996. 291 pp. Foreword by Keith Hart. Tables. Appendix. Selected Bibliography. Index. £42.00. $71.95. Cloth.

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It is well known that after the removal of the template many porous aluminophosphates and related materials are very sensitive to water.' Depending on the type of structure, reversible or irreversible phase transitions, loss of crystallinity and changes in the coordination of some framework A1 upon rehydration are observed. For example, solid-state NMR shows that the rehydration of SAPO-5 leads to the formation of octahedral Al. Subsequent dehydration restores the initial tetrahedral coordination of Al. Template-free SAPO-37 becomes totally amorphous to X-rays after exposure to water and stays so after subsequent thermal treatment^.,,^ In contrast, Barthomeuf and co-workers have shown recently, that, on hydration, template-free SAPO-34, an analogue of chabasite, shows the opening of some Si-0-A1 bonds, the effect being reversible upon dehydrati~n.T~h e hydrated distorted structure was found to be stable for months with no further modifications and the ordered material could be regenerated by removal of water. Here we wish to report that the structure of template-free SAPO-40 undergoes a similar reversible modification.

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Chapter in Merrill, Barbara (ed.) (2009) Learning to Change? The Role of Identity and Learning Careers in Adult Education. Hamburg: Peter Lang Publishers. URL: http://www.peterlang.com/ index.cfm?vID=58279&vLang=E&vHR=1&vUR=2&vUUR=1

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Forecasting future sales is one of the most important issues that is beyond all strategic and planning decisions in effective operations of retail businesses. For profitable retail businesses, accurate demand forecasting is crucial in organizing and planning production, purchasing, transportation and labor force. Retail sales series belong to a special type of time series that typically contain trend and seasonal patterns, presenting challenges in developing effective forecasting models. This work compares the forecasting performance of state space models and ARIMA models. The forecasting performance is demonstrated through a case study of retail sales of five different categories of women footwear: Boots, Booties, Flats, Sandals and Shoes. On both methodologies the model with the minimum value of Akaike's Information Criteria for the in-sample period was selected from all admissible models for further evaluation in the out-of-sample. Both one-step and multiple-step forecasts were produced. The results show that when an automatic algorithm the overall out-of-sample forecasting performance of state space and ARIMA models evaluated via RMSE, MAE and MAPE is quite similar on both one-step and multi-step forecasts. We also conclude that state space and ARIMA produce coverage probabilities that are close to the nominal rates for both one-step and multi-step forecasts.

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The present thesis is a contribution to the debate on the applicability of mathematics; it examines the interplay between mathematics and the world, using historical case studies. The first part of the thesis consists of four small case studies. In chapter 1, I criticize "ante rem structuralism", proposed by Stewart Shapiro, by showing that his so-called "finite cardinal structures" are in conflict with mathematical practice. In chapter 2, I discuss Leonhard Euler's solution to the Königsberg bridges problem. I propose interpreting Euler's solution both as an explanation within mathematics and as a scientific explanation. I put the insights from the historical case to work against recent philosophical accounts of the Königsberg case. In chapter 3, I analyze the predator-prey model, proposed by Lotka and Volterra. I extract some interesting philosophical lessons from Volterra's original account of the model, such as: Volterra's remarks on mathematical methodology; the relation between mathematics and idealization in the construction of the model; some relevant details in the derivation of the Third Law, and; notions of intervention that are motivated by one of Volterra's main mathematical tools, phase spaces. In chapter 4, I discuss scientific and mathematical attempts to explain the structure of the bee's honeycomb. In the first part, I discuss a candidate explanation, based on the mathematical Honeycomb Conjecture, presented in Lyon and Colyvan (2008). I argue that this explanation is not scientifically adequate. In the second part, I discuss other mathematical, physical and biological studies that could contribute to an explanation of the bee's honeycomb. The upshot is that most of the relevant mathematics is not yet sufficiently understood, and there is also an ongoing debate as to the biological details of the construction of the bee's honeycomb. The second part of the thesis is a bigger case study from physics: the genesis of GR. Chapter 5 is a short introduction to the history, physics and mathematics that is relevant to the genesis of general relativity (GR). Chapter 6 discusses the historical question as to what Marcel Grossmann contributed to the genesis of GR. I will examine the so-called "Entwurf" paper, an important joint publication by Einstein and Grossmann, containing the first tensorial formulation of GR. By comparing Grossmann's part with the mathematical theories he used, we can gain a better understanding of what is involved in the first steps of assimilating a mathematical theory to a physical question. In chapter 7, I introduce, and discuss, a recent account of the applicability of mathematics to the world, the Inferential Conception (IC), proposed by Bueno and Colyvan (2011). I give a short exposition of the IC, offer some critical remarks on the account, discuss potential philosophical objections, and I propose some extensions of the IC. In chapter 8, I put the Inferential Conception (IC) to work in the historical case study: the genesis of GR. I analyze three historical episodes, using the conceptual apparatus provided by the IC. In episode one, I investigate how the starting point of the application process, the "assumed structure", is chosen. Then I analyze two small application cycles that led to revisions of the initial assumed structure. In episode two, I examine how the application of "new" mathematics - the application of the Absolute Differential Calculus (ADC) to gravitational theory - meshes with the IC. In episode three, I take a closer look at two of Einstein's failed attempts to find a suitable differential operator for the field equations, and apply the conceptual tools provided by the IC so as to better understand why he erroneously rejected both the Ricci tensor and the November tensor in the Zurich Notebook.

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The distribution of excitation energy between the two photosystems (PSII and PSI) of photosynthesis is regulated by the light state transition. Three models have been proposed for the mechanism of the state transition in phycobilisome (PBS) containing organisms, two involving protein phosphorylation. A procedure for the rapid isolation of thylakoid membranes and PBS fractions from the cyanobacterium Synechococcus m. PCC 6301 in light state 1 and light state 2 was developed. The phosphorylation of thylakoid and soluble proteins rapidly isolated from intact cells in state 1 and state 2 was investigated. 77 K fluorescence emission spectra revealed that rapidly isolated thylakoid membranes retained the excitation energy distribution characteristic of intact cells in state 1 and state 2. Phosphoproteins were identified by gel electrophoresis of both thylakoid membrane and phycobilisome fractions isolated from cells labelled with 32p orthophosphate. The results showed very close phosphoprotein patterns for either thylakoid membrane or PBS fractions in state 1 and state 2. These results do not support proposed models for the state transition which required phosphorylation of PBS or thylakoid membrane proteins.

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The optical cross section of PS I in whole cells of Porphyridium cruentum (UTEX 161), held in either state 1 or state 2, was determined by measuring the change in absorbance at 820nm, an indication of P700+; the X-section of PS2 was determined by measuring the variable fluorescence, (Fv-Fo)/Fo, from PS2. Both cross-sections were 7 determined by fitting Poisson distribution equations to the light saturation curves obtained with single turnover laser flashes which varied in intensity from zero to a level where maximum yield occurred. Flash wavelengths of 574nm, 626nm, and 668nm were used, energy absorbed by PBS, by PBS and chla, and by chla respectively. There were two populations of both PSi and PS2. A fraction of PSi is associated with PBS, and a fraction of PS2 is free from PBS. On the transition S1->S2, only with PBS-absorbed energy (574nm) did the average X-section of PSi increase (27%), and that of PS2 decrease (40%). The fraction of PSi associated with PBS decreased, from 0.65 to 0.35, and the Xsection of this associated PS 1 increased, from 135±65 A2 to 400±300A2. The cross section of PS2 associated with PBS decreased from 150±50 A2 to 85±45 A2, but the fraction of PS2 associated with PBS, approximately 0.75, did not change significantly. The increase in PSi cross section could not be completely accounted for by postulating that several PSi are associated with a single PBS and that in the transition to state2, fewer PSi share the same number of PBS, resulting in a larger X-section. It is postulated that small changes occur in the attachment of PS2 to PBS causing energy to be diverted to the attached PSi. These experiments support neither the mobile-PBS model of state transitions nor that of spillover. From cross section changes there was no evidence of energy transfer from PS2 to PSi with 668nm light. The decrease in PS2 fluorescence which occurred at this wavelength cannot be explained by energy transfer; another explanation must be sought. No explanation was found for an observed decrease in PSi yield at high flash intensities.

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Published under the auspices of "The Literary and Historical Society of Quebec".

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Specific pages with War of 1812 content in this volume: Page 77: The American senate declares war on Great Britain. Click on the pdf links to the right to view the monthly issue. The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. The magazine contains accounts of important historical events, abstracts of foreign occurrences, letters from noted figures, articles on geography, biographical entries for prominent people, poems, statistics, obituaries, reviews of books and more.

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Specific pages with War of 1812 content in this volume: August: Page 179: The official American declaration of war. Click on the pdf links to the right to view the monthly issue. The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. The magazine contains accounts of important historical events, abstracts of foreign occurrences, letters from noted figures, articles on geography, biographical entries for prominent people, poems, statistics, obituaries, reviews of books and more.

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Specific pages related to the War of 1812 include: Pages 655, 656, 657: Battles on the Niagara Frontier, with the death of Major General Sir Isaac Brock at the Battle of Queenston Heights on October 13, 1812. Page 670: Oct 13 - Obituary for Major General Sir Isaac Brock. Click on the pdf links to the right to view the monthly issue. The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. The magazine contains accounts of important historical events, abstracts of foreign occurrences, letters from noted figures, articles on geography, biographical entries for prominent people, poems, statistics, obituaries, reviews of books and more.

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Specific pages related to the War of 1812 include: Pages 282 to 283: Mention of border hostilities, the occupation of the town of Sandwich (in Canada, near Detroit (present day Windsor, Ontario) and a riot in Baltimore. Click on the pdf links to the right to view the monthly issue. The Gentleman's Magazine and Historical Chronicle was a monthly periodical published in England during the years of 1736-1833. The volumes of interest from 1812-1815 were written and compiled by Sylvanus Urban, Gentleman. These volumes were printed in London by Nichols, Son and Bentley at Cicero's Head, Red Lion Passage and Fleet Street. The magazine contains accounts of important historical events, letters from noted figures, articles on geography, biographical entries for prominent people, poems, statistics, obituaries, reviews of books and more.