La apariencia como trans-parencia : una situación existencial del homo poeticus

Resumen: Dostoevskij atribuye a la belleza una función salvífica (“la belleza salvará al mundo”), poniéndola así en relación con el campo afectivo, salvación significa en efecto vida plena; para Matisse “Todo arte digno de tal nombre es religioso”, es decir, posee una función de “mediación-unión” entre órdenes diversos. La noción de “visión interior”, es la que mejor fundamenta estas convicciones. Ella atraviesa el tiempo y el espacio: está presente en la antigua cultura china, así como en la Grecia clásica y en la Antigüedad Tardía y permanece implícita durante todo el Medioevo; se la vuelve a encontrar en alguno de los máximos pintores modernos (Kandinsky, Chagal). Todos los testimonios de los artistas concuerdan en indicar que para alcanzarla es necesario una especie de ascesis: ésta consiste en una revelación, experimentada como un don, del Sentido oculto en lo sensible; por el hecho de dar inicio al pasaje de un nivel ontológico a otro (valencia re-ligiosa o syn-bolica) y de consistir en una experiencia de plenitud de vida, le pertenece además un efecto transformante (valencia afectiva). Esta vía propiamente humana de la “visión interior”, por la cual la apariencia (lo sensible) se vuelve trans-parencia de lo invisible, se presenta como la más adecuada al arte cristiano para el culto.

Ramesside, Late Nubian and christian pottery from Serra West in the Museum of Natural History, La Plata

Resumen: El Museo de Ciencias Naturales de La Plata, Argentina, posee una colección de piezas cerámicas provenientes del asentamiento egipcio y de la iglesia de Aksha, y de las tumbas nubias de Serra Oeste, sobre la margen izquierda del Nilo en la Baja Nubia, que pertenecen a las culturas meroítica y del Grupo X. Esta colección es producto del reparto después de las excavaciones realizadas por la Expedición Franco-Argentina en Sudán entre 1961 y 1963, como parte de las campañas de la UNESCO para salvar los monumentos de Nubia.

Peftjauawybast, king of Nen-nesut : genealogy, art history, and the chronology of late libyan Egypt

This paper argues in detail for the identification of Peftjauawybast, King of Nen-nesut (fl. 728/720 BC ), with Peftjauawybast, High Priest of Ptah in Memphis (fl. c. 790–780 BC2), known from the Apis stela of year 28 of Shoshenq III. This identification ties in with a significant lowering of the accepted dates for the kings from Shoshenq III, Osorkon III and Takeloth III to Shoshenq V, and the material culture associated with them. Such a shift seems to be supported by stylistic and genealogical evidence. As a consequence, it is further suggested that the Master of Shipping at Nen-nesut, Pediese i, was perhaps related by descent and marriage to the family of the High Priests of Memphis and King Peftjauawybast.

Profit and Cost in "Modern" Post-Marxian Profit Theory: A Case Study from Varian's "Intermediate Microeconomics"

In this paper, I examine the treatment of competitive profit of professor Varian in his textbook on Microeconomics, as a representative of the “modern” post-Marxian view on competitive profit. I show how, on the one hand, Varian defines profit as the surplus of revenues over cost and, thus, as a part of the value of commodities that is not any cost. On the other hand, however, Varian defines profit as a cost, namely, as the opportunity cost of capital, so that, in competitive conditions, the profit or income of capital is determined by the opportunity cost of capital. I argue that this second definition contradicts the first and that it is based on an incoherent conception of opportunity cost.

Guided pollards in the Basque Country (Spain) during the Early Modern Ages

Publicado en: "End of Tradition?.Part 1 : History of Commons and Commons Management (Cultural Severance and Commons Past)", edited by Ian D. Rotherham, Mauro Agnoletti and Christine Handley

Stock assessment of the Atlantic menhaden, Brevoortia tyrannus, fishery

A stock assessment of the Atlantic menhaden, Brevoortia tyrannus, fishery was conducted with purse-seine landings data from 1940 to 1984 and port sampling data from 1955 to 1984. These data were analyzed to determine growth rates, maximum sustainable yield (MSY), spawner-recruit relationships, and yield per recruit. Virtual population analysis was used to estimate stock size, year class size, and fishing mortality rates. Surplus production models produced estimates of MSY from 450 to 490 kmt compared with yields of 416to 436 kmt based roughly on maximum recruitment from a weak spawner-recruit relationship. Recruitment to age-I ranged from 1.2 to 14.8 billion fish for year classes 1955-81. Recent mean recruitment to age-I for the 1975-81 year classes averaged 5.7 billion fish and compared favorably with the mean of 7.7 billion age-I fish recruited during the late 1950's. Mean recruitment from recent years suggests possible coastwide yields of 416 to 481 kmt. Continued dominance of late age-2 spawners among the spawning stock is of concern, since the stock is at greater risk through poor recruitment if recent favorable environmental conditions change. Yield-per-recruit estimates ranged from 46 g to 59 g since 1970. The high dependency of the modern fishery on prespawners has increased concerns about fluctuations in year-to-year availability and catches. To increase yield and enhance the stability of the resource, the number of age classes contributing significantly to the fishery should be increased, creating a butTer against future poor recruitment years and lessening the year-to-year fluctuations in landings. (PDF file contains 24 pages.)

Modern aquaculture practices for increased fish production in Nigeria

Various modern aquaculture practices applied in fish production especially in Asia are reviewed. The vast Nigerian aquatic medium of numerous water bodies like rivers, streams, lakes reservoirs, flood plains, irrigation canals, coastal swamps offer great potentials for aquaculture production, if optimally utilized. Constraints to modernization of aquaculture in Nigeria among other factors are: 1) a serious shortage of trained manpower; 2) lack of knowledge on profitability of aquaculture as an industry; 3) limited availability of fund (or capital); 4) non-recognition of indigenous trained aquaculture personnel; 5) inadequate data base on the biology and ecological requirements of endemic fish species with aquaculture potentials; 6) insufficient data on production and management techniques; and 7) lack of rational aquaculture development planning. Recommendations are made towards combating these constraints

Characterization of diverse megathrust fault behavior related to seismic supercycles, Mentawai Islands, Sumatra

Long paleoseismic histories are necessary for understanding the full range of behavior of faults, as the most destructive events often have recurrence intervals longer than local recorded history. The Sunda megathrust, the interface along which the Australian plate subducts beneath Southeast Asia, provides an ideal natural laboratory for determining a detailed paleoseismic history over many seismic cycles. The outer-arc islands above the seismogenic portion of the megathrust cyclically rise and subside in response to processes on the underlying megathrust, providing uncommonly good illumination of megathrust behavior. Furthermore, the growth histories of coral microatolls, which record tectonic uplift and subsidence via relative sea level, can be used to investigate the detailed coseismic and interseismic deformation patterns. One particularly interesting area is the Mentawai segment of the megathrust, which has been shown to characteristically fail in a series of ruptures over decades, rather than a single end-to-end rupture. This behavior has been termed a seismic “supercycle.” Prior to the current rupture sequence, which began in 2007, the segment previously ruptured during the 14th century, the late 16th to late 17th century, and most recently during historical earthquakes in 1797 and 1833. In this study, we examine each of these previous supercycles in turn.

First, we expand upon previous analysis of the 1797–1833 rupture sequence with a comprehensive review of previously published coral microatoll data and the addition of a significant amount of new data. We present detailed maps of coseismic uplift during the two great earthquakes and of interseismic deformation during the periods 1755–1833 and 1950–1997 and models of the corresponding slip and coupling on the underlying megathrust. We derive magnitudes of Mw 8.7–9.0 for the two historical earthquakes, and determine that the 1797 earthquake fundamentally changed the state of coupling on the fault for decades afterward. We conclude that while major earthquakes generally do not involve rupture of the entire Mentawai segment, they undoubtedly influence the progression of subsequent ruptures, even beyond their own rupture area. This concept is of vital importance for monitoring and forecasting the progression of the modern rupture sequence.

Turning our attention to the 14th century, we present evidence of a shallow slip event in approximately A.D. 1314, which preceded the “conventional” megathrust rupture sequence. We calculate a suite of slip models, slightly deeper and/or larger than the 2010 Pagai Islands earthquake, that are consistent with the large amount of subsidence recorded at our study site. Sea-level records from older coral microatolls suggest that these events occur at least once every millennium, but likely far less frequently than their great downdip neighbors. The revelation that shallow slip events are important contributors to the seismic cycle of the Mentawai segment further complicates our understanding of this subduction megathrust and our assessment of the region’s exposure to seismic and tsunami hazards.

Finally, we present an outline of the complex intervening rupture sequence that took place in the 16th and 17th centuries, which involved at least five distinct uplift events. We conclude that each of the supercycles had unique features, and all of the types of fault behavior we observe are consistent with highly heterogeneous frictional properties of the megathrust beneath the south-central Mentawai Islands. We conclude that the heterogeneous distribution of asperities produces terminations and overlap zones between fault ruptures, resulting in the seismic “supercycle” phenomenon.

Dating and characterizing late holocene earthquakes using paleomagnetics

In this thesis I apply paleomagnetic techniques to paleoseismological problems. I investigate the use of secular-variation magnetostratigraphy to date prehistoric earthquakes; I identify liquefaction remanent magnetization (LRM), and I quantify coseismic deformation within a fault zone by measuring the rotation of paleomagnetic vectors.

In Chapter 2 I construct a secular-variation reference curve for southern California. For this curve I measure three new well-constrained paleomagnetic directions: two from the Pallett Creek paleoseismological site at A.D. 1397-1480 and A.D. 1465-1495, and one from Panum Crater at A.D. 1325-1365. To these three directions I add the best nine data points from the Sternberg secular-variation curve, five data points from Champion, and one point from the A.D. 1480 eruption of Mt. St. Helens. I derive the error due to the non-dipole field that is added to these data by the geographical correction to southern California. Combining these yields a secular variation curve for southern California covering the period A.D. 670 to 1910, with the best coverage in the range A.D. 1064 to 1505.

In Chapter 3 I apply this curve to a problem in southern California. Two paleoseismological sites in the Salton trough of southern California have sediments deposited by prehistoric Lake Cahuilla. At the Salt Creek site I sampled sediments from three different lakes, and at the Indio site I sampled sediments from four different lakes. Based upon the coinciding paleomagnetic directions I correlate the oldest lake sampled at Salt Creek with the oldest lake sampled at Indio. Furthermore, the penultimate lake at Indio does not appear to be present at Salt Creek. Using the secular variation curve I can assign the lakes at Salt Creek to broad age ranges of A.D. 800 to 1100, A.D. 1100 to 1300, and A.D. 1300 to 1500. This example demonstrates the large uncertainties in the secular variation curve and the need to construct curves from a limited geographical area.

Chapter 4 demonstrates that seismically induced liquefaction can cause resetting of detrital remanent magnetization and acquisition of a liquefaction remanent magnetization (LRM). I sampled three different liquefaction features, a sandbody formed in the Elsinore fault zone, diapirs from sediments of Mono Lake, and a sandblow in these same sediments. In every case the liquefaction features showed stable magnetization despite substantial physical disruption. In addition, in the case of the sandblow and the sandbody, the intensity of the natural remanent magnetization increased by up to an order of magnitude.

In Chapter 5 I apply paleomagnetics to measuring the tectonic rotations in a 52 meter long transect across the San Andreas fault zone at the Pallett Creek paleoseismological site. This site has presented a significant problem because the brittle long-term average slip-rate across the fault is significantly less than the slip-rate from other nearby sites. I find sections adjacent to the fault with tectonic rotations of up to 30°. If interpreted as block rotations, the non-brittle offset was 14.0+2.8, -2.1 meters in the last three earthquakes and 8.5+1.0, -0.9 meters in the last two. Combined with the brittle offset in these events, the last three events all had about 6 meters of total fault offset, even though the intervals between them were markedly different.

In Appendix 1 I present a detailed description of my standard sampling and demagnetization procedure.

In Appendix 2 I present a detailed discussion of the study at Panum Crater that yielded the well-constrained paleomagnetic direction for use in developing secular variation curve in Chapter 2. In addition, from sampling two distinctly different clast types in a block-and-ash flow deposit from Panum Crater, I find that this flow had a complex emplacement and cooling history. Angular, glassy "lithic" blocks were emplaced at temperatures above 600° C. Some of these had cooled nearly completely, whereas others had cooled only to 450° C, when settling in the flow rotated the blocks slightly. The partially cooled blocks then finished cooling without further settling. Highly vesicular, breadcrusted pumiceous clasts had not yet cooled to 600° C at the time of these rotations, because they show a stable, well clustered, unidirectional magnetic vector.

Chelation-enforced metal-arene interactions : insights into substrate binding and catalysis by late transition metal complexes

Understanding and catalyzing chemical reactions requiring multiple electron transfers is an endeavor relevant to many outstanding challenges in the field of chemistry. To study multi-electron reactions, a terphenyl diphosphine framework was designed to support one or more metals in multiple redox states via stabilizing interactions with the central arene of the terphenyl backbone. A variety of unusual compounds and reactions and their relevance toward prominent research efforts in chemistry are the subject of this dissertation.

Chapter 2 introduces the para-terphenyl diphosphine framework and its coordination chemistry with group 10 transition metal centers. Both mononuclear and dinuclear compounds are characterized. In many cases, the metal center(s) are stabilized by the terphenyl central arene. These metal–arene interactions are characterized both statically, in the solid state, and fluxionally, in solution. As a proof-of-principle, a dinickel framework is shown to span multiple redox states, showing that multielectron chemistry can be supported by the coordinatively flexible terphenyl diphosphine.

Chapter 3 presents reactivity of the terphenyl diphosphine when bound to a metal center. Because of the dearomatizing effect of the metal center, the central arene of the ligand is susceptible to reactions that do not normally affect arenes. In particular, Ni-to-arene H-transfer and arene dihydrogenation reactions are presented. Additionally, evidence for reversibility of the Ni-to-arene H-transfer is discussed.

Chapter 4 expands beyond the chelated metal-arene interactions of the previous chapters. A dipalladium(I) terphenyl diphosphine framework is used to bind a variety of exogenous organic ligands including arenes, dienes, heteroarenes, thioethers, and anionic ligands. The compounds are structurally characterized, and many ligands exhibit unprecedented bindng modes across two metal centers. The relative binding affinities are evaluated spectroscopically, and equilibrium binding constants for the examined ligands are determined to span over 13 orders of magnitude. As an application of this framework, mild hydrogenation conditions of bound thiophene are presented.

Chapter 5 studies nickel-mediated C–O bond cleavage of aryl alkyl ethers, a transformation with emerging applications in fields such as lignin biofuels and organic methodology. Other group members have shown the mechanism of C–O bond cleavage of an aryl methyl ether incorporated into a meta-terphenyl diphosphine framework to proceed through β-H elimination of an alkoxide. First, the electronic selectivity of the model system is examined computationally and compared with catalytic systems. The lessons learned from the model system are then applied to isotopic labeling studies for catalytic aryl alkyl ether cleavage under dihydrogen. Results from selective deuteration experiments and mass spectrometry draw a clear analogy between the mechanisms of the model and catalytic systems that does not require dihydrogen for C–O bond cleavage, although dihydrogen is proposed to play a role in catalyst activation and catalytic turnover.

Appendix A presents initial efforts toward heterodinuclear complexes as models for CO dehydrogenase and Fischer Tropsch chemistry. A catechol-incorporating terphenyl diphosphine is reported, and metal complexes thereof are discussed.

Appendix B highlights some structurally characterized terphenyl diphosphine complexes that either do not thematically belong in the research chapters or proved to be difficult to reproduce. These compounds show unusual coordination modes of the terphenyl diphosphine from which other researchers may glean insights.

Análisis del mercado eléctrico en Escandinavia: NORD POOL

La electricidad es un elemento muy importante para la sociedad y cada vez se depende más para la vida moderna y el trabajo. Como consecuencia, el consumo de electricidad ha crecido año a año y por lo tanto, la producción también ha aumentado. Esto ha provocado que los países estén interconectados entre sí para poder satisfacer la demanda de electricidad. Esta situación ha llevado a la formación del mayor mercado a nivel global de intercambio de electricidad. Este trabajo tiene como objetivo analizar el mercado eléctrico de los países de Noruega, Suecia, Finlandia y Dinamarca y el análisis de los precios de la electricidad. Los resultados sugieren que los precios de la electricidad son muy volátiles, es por ello que en invierno la media de los precios es más alta y en verano es más baja.

Análisis del mercado eléctrico en Escandinavia: NORD POOL

La electricidad es un elemento muy importante para la sociedad y cada vez se depende más para la vida moderna y el trabajo. Como consecuencia, el consumo de electricidad ha crecido año a año y por lo tanto, la producción también ha aumentado. Esto ha provocado que los países estén interconectados entre sí para poder satisfacer la demanda de electricidad. Esta situación ha llevado a la formación del mayor mercado a nivel global de intercambio de electricidad. Este trabajo tiene como objetivo analizar el mercado eléctrico de los países de Noruega, Suecia, Finlandia y Dinamarca y el análisis de los precios de la electricidad. Los resultados sugieren que los precios de la electricidad son muy volátiles, es por ello que en invierno la media de los precios es más alta y en verano es más baja.