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121.
The contested spaces of Cuban development: Post-socialism, post-colonialism and the geography of transition 总被引:1,自引:0,他引:1
Simon Reid-Henry 《Geoforum》2007,38(3):445-455
The experience of the (post)socialist South has been marginal to the study of transition, despite the many similarities between processes of transition and development. This paper tries to better understand this overlap by exploring some empirical and conceptual connections between processes of development and processes of transition in Cuba. In doing so it makes two sets of arguments. The first set of arguments concerns the nature of ‘transition’ itself. I use the ‘contested spaces’ of the Cuban (socialist) biotech sector, and specifically its attempts to attract foreign (capitalist) investment as a case study. As a high profile industry, biotechnology functioned in Cuba as a political space within which questions of transition and development could be reconfigured by blurring the boundaries between them. In turn, this has enabled the Cuban State to legitimise responses to transition that would otherwise have appeared contradictory. The second set of arguments try to explain how this was possible. I argue that the slippage between nationalist and socialist visions of development allowed biotechnology (as a specifically developmentalist project) to be variously understood as, for example, a post-colonial socialist, or anti-colonial nationalist project in ways that suited the needs of transition at any one time. Such recombinations in many ways account for the non-linear and reversible nature of transition in Cuba. I speculate as to whether Bruno Latour’s work on the way capitalist societies understand themselves to be ‘modern’, helps explain how, in (post)socialist countries, processees of transition can be shaped through different historical constructions of modernisation and development. 相似文献
122.
Johnson Simon P.; de Waele Bert; Tembo Francis; Katongo Crispin; Tani Kenichiro; Chang Qing; Iizuka Tsuyoshi; Dunkley Daniel 《Journal of Petrology》2007,48(7):1411-1441
The southern Irumide Belt (SIB) is an ENEWSW-trending,late Mesoproterozoic orogenic belt located between the CongoTanzaniaBangweulu(CTB) and Kalahari cratons in central southern Africa. It isseparated from the late Mesoproterozoic Irumide Belt (IB) tothe north by Permo-Triassic graben, raising the possibilitythat the younger rifts reactivated a suture between the twobelts that has been rendered cryptic as a result of youngerKaroo cover. Both belts are dominated by calc-alkaline gneisses,but in addition the SIB contains abundant metavolcanic and metasedimentaryrocks. In this study we present detailed geochemical, isotopicand geochronological data for volcanic and plutonic lithologiesfrom the southernmost part of the SIB, the CheworeRufunsaTerrane. This terrane comprises a wide variety of supracrustalto mid-crustal rocks that have major- and trace-element compositionssimilar to magmas formed in present-day subduction zones. Chondrite-normalizedrare earth element (REE) profiles and whole-rock SmNdisotope compositions indicate that the parental supra-subductionmelts interacted with, and were contaminated by sialic continentalcrust, implying a continental-margin-arc setting. Secondaryionization mass spectrometry dating of magmatic zircon has yieldedcrystallization ages between c. 1095 and 1040 Ma, similar toelsewhere in the SIB. UPb dating and in situ LuHfisotopic analyses of abundant xenocrystic zircon extracted fromthe late Mesoproterozoic granitoids indicate that the contaminantcontinental basement was principally Palaeoproterozoic in ageand had a juvenile isotopic signature at the time of its formation.These data are in contrast to those for the IB, which is characterizedby younger, c. 1020 Ma, calc-alkaline gneisses that formed bythe direct recycling of Archaean crust without significant additionof any juvenile material. We suggest that the SIB developedby the subduction of oceanic crust under the margin of an unnamedcontinental mass until ocean closure at c. 1040 Ma. Subsequentcollision between the SIB and the CTB margin led to the cessationof magmatism in the SIB and the initiation of compression andcrustal melting in the IB. KEY WORDS: geochemistry; Mesoproterozoic; SHRIMP zircon UPb dating; SmNd isotopes; Southern Irumide Belt 相似文献
123.
Gérard Thuillier Michel Hersé Paul C. Simon Dietrich Labs Holger Mandel Didier Gillotay Thomas Foujols 《Solar physics》1998,177(1-2):41-61
The SOLSPEC instrument has been built to carry out solar spectral irradiance measurements from 200 to 3000 nm. It consists of three spectrometers designed to measure the solar spectral irradiance in ultraviolet, visible, and infrared domains. It flew with the ATLAS I mission in March 1992. This paper is dedicated to the visible part of the solar spectrum. Comparisons with recent data are shown and differences below 450 nm are discussed. 相似文献
124.
Ignimbrites of the 13-ka Upper Laacher See Tephra were deposited from small, highly concentrated, moderately fluidized pyroclastic
flows. Their unconsolidated nature, and the prominence of accidental Devonian slate fragments, make these ignimbrites ideal
for clast fabric studies. The upper flow unit of ignimbrite M14 has characteristics typical of a type-2 ignimbrite. Layer
2a and the lower part of layer 2b of the flow unit have strong, upstream-inclined a[p] fabrics (a[p] means long particle axes
parallel to flow direction). Only clasts with a/b axial ratios of 2.5 or greater preserve good a[p] fabrics, whereas the a–b
planes of flat fragments dip upstream irrespective of axial ratio. The a-axis fabric becomes weaker, flatter, and more girdle-like
in the upper half of layer 2b. At one locality the a-axis fabric appears to rotate 40° up through the flow unit, suggesting
either shear decoupling of different levels in the moving flow or unsteadiness effects in a flow depositing progressively
at its base. The existence of similarly strong a[p] fabrics in layer 2a and the lower half of layer 2b appears inconsistent
with the common interpretation that ignimbrite flow units are emplaced as a plug of essentially non-shearing material (layer
2b) on a thin shear layer (layer 2a), and that the entire flow freezes en masse to form the deposit. The data suggest that,
if the flow froze en masse, it was shearing pervasively through at least half its thickness. Another possibility is that the
flow unit aggraded progressively from the base up, and that the fabrics record the integrated history of shear directions
and intensities immediately above the bed throughout the duration of deposition.
Received: 13 February 1997 / Accepted: 4 April 1998 相似文献
125.
Simon D. Vanstone 《Sedimentology》1998,45(1):19-37
Palaeokarst is an important feature of late Dinantian exposure surfaces. Soil-filled depressions are widely developed. These are comparable to modern day solution dolines and were probably interspersed by areas of relatively bare limestone pavement. The palaeokarst primarily exhibits a smooth, mamillated to potholed surface form, consistent with its formation beneath a soil cover. Areas between the depressions have been extensively stylolitised and would likely have originally been characterized by small-scale fretted and sculpted karren forms typical of subaerial karstification. Palaeokarst pits making up the depressions are thought to have been initiated through stem-flow drainage from trees. Rain water, intercepted by the crown of the tree, was concentrated at specific sites on the emergent surface and dissolution beneath the trunk produced cylindrical pits that propagated vertically downwards. Trees responsible for concentrating drainage may also have enhanced the acidic nature of the rain water through leaching of organic acids from foliar and woody tissues. Downward propagation of the pits was limited to the uppermost 1–2 m and enlargement primarily occurred through lateral amalgamation of adjacent pits. Once initiated, continued development of the depressions would have been self perpetuating; the preferential accumulation of volcanic ash and organic matter enhancing water retention and encouraging further vegetation growth. In contrast, intervening areas would have been characterized by slow vertical denudation only. Karstification likely took of the order of a few hundred years in the case of potholed palaeokarstic surfaces formed solely by stem-flow drainage, to a few tens of thousands of years where the palaeokarst is more mature. 相似文献
126.
Scapolite–wollastonite–grossular bearing calc-silicate rocks from the Vellanad area in the Kerala Khondalite Belt (KKB) of Southern India preserve a number of reaction textures which help to deduce their P–T–fluid history. Textures include calcite+plagioclase±quartz symplectites after scapolite, grossular+quartz coronas between wollastonite and plagioclase, grossular coronas between wollastonite and plagioclase+calcite that replace former scapolite, and grossular blebs replacing anorthite+calcite+quartz pseudomorphs of scapolite. Garnet coronas are also observed between clinopyroxene and wollastonite or scapolite or plagioclase. The reactions, apart from those involving clinopyroxene, can be modelled in the simple CaO–Al2O3–SiO2–CO2 system and interpreted using partial reaction grids constructed for the activities of end-members in the analysed phases. The reaction topologies produced are good approximations for the peak as well as retrograde mineral assemblages and reaction textures. For the compositions of the phases present in this study, the medium pressure calc-silicate assemblages are defined by the stable pseudo-invariant points [Qtz], [Mei] and [Grs]. The textural features interpreted using these activity-corrected grids indicate a phase of isobaric cooling from about 835°C to 750°C at 6 kbar in the Vellanad area. This is inconsistent with earlier studies on other lithologies from the KKB, most of which imply a post-peak P–T path involving near-isothermal decompression. However, as the temperatures obtained for the KKB from the calc-silicates are higher than those previously deduced from metapelites and garnet–orthopyroxene assemblages, the phase of near-isobaric cooling reported here is inferred to have proceeded prior to the onset of the decompression documented from studies of other rock types. 相似文献
127.
M.Unavane GerardGilmore N.Epchtein G.Simon D.Tiphène B.de Batz 《Monthly notices of the Royal Astronomical Society》1998,295(1):119-144
We present the analysis of three-colour optical/near-infrared images, in IJK , taken for the DEep Near Infrared Southern Sky Survey (DENIS) project. The region considered covers 17.4 deg2 and lies within <5°, b <1.°5. The adopted methods for deriving photometry and astrometry in these crowded images, together with an analysis of the deficiencies nevertheless remaining, are presented. The numbers of objects extracted in I , J and K are 748 000, 851 000 and 659 000 respectively, to magnitude limits of 17, 15 and 13. Eighty per cent completeness levels typically fall at magnitudes 16, 13 and 10 respectively, fainter by about 2 mag than the usual DENIS limits as a result of the crowded nature of these fields. A simple model to describe the disc contribution to the number counts is constructed, and parameters for the dust layer are derived. We find that a formal fit of parameters for the dust plane, from these data in limited directions, gives a scalelength and scaleheight of 3.4±1.0 kpc and 40±5 pc respectively, and a solar position 14.0±2.5 pc below the plane. This latter value is likely to be affected by localized dust asymmetries. We convolve a detailed model of the systematic and random errors in the photometry with a simple model of the Galactic disc and dust distribution to simulate expected colourmagnitude diagrams. These are in good agreement with the observed diagrams, allowing us to isolate those stars from the inner disc and bulge. After correcting for local dust-induced asymmetries, we find evidence for longitude-dependent asymmetries in the distant J and K sources, consistent with the general predictions of some Galactic bar models. We consider complementary L -band observations in the companion paper. 相似文献
128.
Volker Springel & Simon D. M. White 《Monthly notices of the Royal Astronomical Society》1998,298(1):143-152
A new method is presented to obtain a non-parametric maximum likelihood estimate of the luminosity function and the selection function of a flux-limited redshift survey. The method parametrizes the selection function as a series of stepwise power laws and allows possible evolution of the luminosity function. We also propose a new technique to estimate the rate of evolution of the luminosity function. This is based on a minimization of the observed large-scale power with respect to the evolutionary model. We use an ensemble of mock surveys extracted from an N -body simulation to verify the power of this method. We apply our estimators to the 1.2-Jy survey of IRAS galaxies. We find a far-infrared luminosity function in good agreement with previously published results and evidence for rather strong evolution. If the comoving number density of IRAS galaxies is assumed to scale ∝ (1 + z ) P , we estimate P = 4.3 ± 1.4. 相似文献
129.
C. Simon Jeffery & Don L. Pollacco 《Monthly notices of the Royal Astronomical Society》1998,298(1):179-184
Intermediate dispersion spectroscopy of a sample of 40 hot subdwarf B stars between 5500 and 9000Å has been obtained. The sample includes a large fraction of targets which have been studied photometrically. Seven targets show strong lines arising from the infrared Ca ii triplet, the unequivocal signature of a cool companion. The positive Ca ii identifications include known photometric binaries and new targets; all are associated with a photometric red excess. Assuming a canonical value for the subdwarf luminosity, all of the detected companions are overluminous compared with the main sequence. The detection procedure indicates an improved and more secure method for the measurement of the binary frequency of hot subdwarfs. 相似文献
130.
Simon J. Woodings rew J. Williams Ralph Martin Ronald R. Burman & David G. Blair 《Monthly notices of the Royal Astronomical Society》1998,301(1):L5-L9
Following the proposal by Damineli that the central object of Eta Carinae may be an early-type binary, we perform numerical simulations of the X-ray emission from colliding stellar winds. A synthetic light curve has been generated which qualitatively agrees with the recent X-ray variability, and provides further support for the binary model. In particular, the model predicts a rise in the observed X-ray emission towards periastron, followed by a sharp drop and subsequent recovery. This is indeed what is seen in the RXTE light curve, although some problems concerning the X-ray spectrum at periastron still need to be explained. The simulations suggest that the width of the periastron dip will provide strong constraints on the binary and stellar wind properties of the components of Eta Car. 相似文献