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Main Phases (main + phase)
Selected AbstractsAssessment of the Tilting Properties of the Human Mitral Valve during Three Main Phases of the Heart Cycle: An Echocardiographic StudyECHOCARDIOGRAPHY, Issue 4 2006Daniel Vanhercke B.N., N.F.E.S.C., R.D.C.S. Rationale and Objectives: In experimental models of the left heart, the mitral valve (MV) is commonly implanted perpendicular to a central axis of the apex/MV. To adapt this to a more correct anatomical model, as well as for further studies of the left ventricle, we created a database of implantation angles of the MV and annulus during three main phases of the heart cycle, based on standard cardiac ultrasound measurements. Materials and Methods: Twenty-eight patients were studied with the standard cardiac ultrasound equipment. From the apical echo window, an anteroposterior (AP) plane and a perpendicular commisure-commisure (CC) plane were generated during three critical moments in the heart cycle: systole (S); diastole early filling (E); and diastole late filling (A). In both planes, the angles between the annular plane and each mitral leaflet, as well as the angle between a theoretical longitudinal axis through the apex and center of the MV orifice and the mitral annulus plane, were measured with a custom-made application of Matlab R14. Results: We observed an inclination of the angle mitral annulus/central left ventricle axis, with its lowest point in the direction of the aortic valve (AP plane) of 85°± 7° in systole (S), 88°± 8° in early diastole (E), and 88°± 7° in late diastole (A). In the CC plane, we observed an almost horizontal implantation of 91°± 5° in systole (S), 91°± 8° in early diastole (E), and 91°± 7° in late diastole (A). [source] Recent channel adjustments in alluvial rivers of Tuscany, central ItalyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2003Massimo RinaldiArticle first published online: 19 JUN 200 Abstract Drastic channel adjustments have affected the main alluvial rivers of Tuscany (central Italy) during the 20th century. Bed-level adjustments were identified both by comparing available topographic longitudinal profiles of different years and through field observations. Changes in channel width were investigated by comparing available aerial photographs (1954 and 1993,98). Bed incision represents the dominant type of vertical adjustment, and is generalized along all the fluvial systems investigated. The Arno River system is the most affected by bed-level lowering (up to 9 m), whereas lower incision (generally less than 2 m) is observed along the rivers of the southern part of the region. Human disturbances appear to be the dominant factors of adjustments: the main phase of vertical change occurred during the period 1945,80, in concomitance with the phase of maximum sediment mining activity at the regional scale. The second dominant type of adjustment that involved most of the rivers in the region consists of a narrowing of the active channel. Based on measurements of channel width conducted on aerial photographs, 38% of the reaches analysed experienced a narrowing greater than 50% of the initial channel width. The largest values of channel narrowing were observed along initially braided or sinuous with alternate bars morphologies in the southern portion of the region. A regional scheme of channel adjustments is derived, based on initial channel morphology and on the amounts of incision and narrowing. Different styles of channel adjustments are described. Rivers that were originally sinuous with alternate bars to braided generally became adjusted by a moderate incision and a moderate to intense narrowing; in contrast, sinuous-meandering channels mainly adjusted vertically, with a minor amount of narrowing. Copyright © 2003 John Wiley & Sons, Ltd. [source] Voltage fluctuation compensator for ShinkansenELECTRICAL ENGINEERING IN JAPAN, Issue 4 2008Tetsuo Uzuka Abstract In AC electric railways, three-phase voltage is changed into the single-phase circuit of two circuits with the Scott-connected transformer. If unbalancing of the load between single-phase circuits becomes large, voltage fluctuation becomes large on the three-phase side. Railway static power conditioner (RPC) was developed for the purpose of controlling voltage fluctuation on the three-phase side. An RPC is comprised of a pair of self-commutated PWM inverters. These inverters connect the main phase and teaser feeding buses, coupled with a DC side capacitor such as a back-to-back (BTB) converter. In this way, the two self-commutated inverters can act as a static var compensator (SVC) to compensate for the reactive power and as an active power accommodator from one feeding bus to another. 20 MVA/60 kV RPCs started commercial operation in 2002 at each two substations on the newly extended Tohoku Shinkansen for compensating voltage fluctuation on the three-phase side caused by traction loads, absorbing harmonic current. The results of operational testing indicate that an RPC can accommodate single-phase loads such as those of PWM-controlled Shinkansen and thyristor phase-controlled Shinkansen, and handle the exciting rush current of transformers, as well as compensate for harmonics successfully. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(4): 25,34, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20397 [source] The orientation and dynamics of cell division within the plane of the developing vertebrate retinaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2004Marc S. Tibber Abstract The orientation of a dividing cell within the plane of the tissue plays an essential role in regulating cell fate in a range of developing structures. To assess its potential role in the developing vertebrate retina we used standard confocal microscopy of fixed tissue and time-lapse confocal imaging of living tissue to examine the orientation of cell division and mitotic spindle rotation within the plane of the retinal neuroepithelium. Based on the study of three rat strains and chick, we report in contrast to recent findings that during the main phase of cell production (E18,P4 in the rat and E6,E11 in the chick) dividing cells are randomly orientated with respect to key anatomical landmarks as well as the orientation of their dividing neighbours. Results from live imaging of neonatal rat retinae support these findings and suggest that unlike the developing cortex, in which metaphase plates often rotate extensively before coming to rest in anaphase, retinal mitotic spindle rotations prior to cell division are minimal. Furthermore, the orientation of metaphase entry largely defines that which is finally adopted during anaphase. Hence, the dynamics of metaphase progression through to anaphase in the retina appear to differ markedly from the brain, and cell divisions within the plane of the tissue are randomly orientated. These results contribute to a growing body of evidence that suggests that the current paradigm with respect to asymmetric division derived from the study of invertebrates cannot be generalized to the developing vertebrate nervous system. [source] Geothermal activity at the archaeological site of Aghia Kyriaki and its significance to Roman industrial mineral exploitation on Melos, GreeceGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 3 2003A. J. Hall The geothermal setting of the archaeological site at Aghia Kyriaki, Southeast Melos (or Milos) was investigated in order to help clarify the possible role of the site in mineral exploitation on Melos in Roman times. There are active sulfurous fumaroles in the area and these were also potential sources of sulfur and alum-group minerals in Roman times. However, geothermal activity has been ongoing in Southeast Melos for hundreds of thousands of years, and extensive hydrothermal alteration of basement rocks to the northeast of the site has produced "white rocks" containing additional potential industrial minerals such as kaolin and alunite. The archaeological remains occur within, but mainly near the surface, of a deeply gullied sequence of late Quaternary alluvial sediments, which consist mainly of metamorphic detritus but are rich in sulfates; the remains contain pottery sherds through the entire sequence of about 40 m. They were deposited on an earlier gullied topography of felsic tuffs overlying the metamorphic basement. Pervasive and veinlike intense reddish alteration of these sediments is probably mainly due to superheated fluid escaping from depth. Field observations demonstrate that this took place after the main phase of building but was likely to be ongoing during occupation of the site. While industrial minerals and geothermal energy would therefore have been available in the Roman period, any relationship of the site to mineral exploitation will have to be determined by archaeological excavation. © 2003 Wiley Periodicals, Inc. [source] The use of simulation and post-simulation interview to examine the knowledge involved in community nursing assessment practiceJOURNAL OF ADVANCED NURSING, Issue 5 2000Alison Bryans PhD MSc BA DipHV RGN RNT The use of simulation and post-simulation interview to examine the knowledge involved in community nursing assessment practice This paper describes the development of an innovative research approach which used the complementary methods of simulation and post-simulation interview to examine the knowledge-base involved in community nursing assessment practice in the United Kingdom. The study commenced in 1994 and the main phase of data-gathering took place over a 3-week period in 1995. Having outlined the study's aim, context and theoretical background, this paper focuses on the two main methods of data-gathering used. Detailed description of the simulation method and the post-simulation interview and the rationales for their use are followed by critical discussion which identifies their particular strengths and weaknesses. Threats to validity are also considered. It is argued that the combined use of a simulated assessment and a post-simulation structured interview has great potential as a means of exploring the knowledge involved in community nursing assessment practice. [source] Performance of fractionating reactors in the absence of rate limitationsJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2004Jeroen L den Hollander Abstract A fractionating reactor for equilibrium-limited reactions is studied theoretically. Reactant A is fed in the center of the countercurrent fractionating system. Product P is effectively transported with the auxiliary phase, while product Q is effectively transported with the main phase, in which the reaction takes place. Model calculations were based on partition and reaction equilibrium at all stages. These show that if the initial reactant concentration and the flow rates are properly selected, the extent of conversion will significantly exceed the corresponding batch conversion. To approach complete conversion in the fractionating reactor, and to recover both products in a pure form, net transport of reactant in either of the countercurrent directions should be prevented. However, irrespective of the number of equilibrium stages, this situation cannot be fully reached when the reactant feed stream is too large (compared with the main and auxiliary streams). Nonetheless, one of the two products may be recovered in a pure form even for such large feed streams. Copyright © 2004 Society of Chemical Industry [source] High-Q Microwave Dielectrics in the (Mg1,xCox)2TiO4 CeramicsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 2 2009Cheng-Liang Huang The microwave dielectric properties and the microstructures of (Mg1,xCox)2TiO4 ceramics prepared by the conventional solid-state route were investigated. Lattice parameters were also measured for specimens with different x. The formation of solid solution (Mg1,xCox)2TiO4 (x=0.02,0.1) was confirmed by the X-ray diffraction patterns, energy dispersive X-ray analysis, and the lattice parameters measured. By increasing x from 0 to 0.05, the Q×f of the specimen can be tremendously boosted from 150 000 GHz to a maximum of 286 000 GHz. A fine combination of microwave dielectric properties (,r,15.7, Q×f,286 000 GHz at 10.4 GHz, ,f,,52.5 ppm/°C) was achieved for (Mg0.95Co0.05)2TiO4 ceramics sintered at 1390°C for 4 h. Ilmenite-structured (Mg0.95Co0.05)TiO3 was detected as a second phase. The presence of the second phase would cause no significant variation in the dielectric properties of the specimen because it possesses compatible properties compared with that of the main phase. In addition, only a small deviation in the dielectric properties was monitored for specimens with x=0.04,0.05 at 1360°,1420°C. It not only provides a wide process window but also ensures an extremely reliable material proposed as a very promising dielectric for low-loss microwave and millimeter wave applications. [source] Sparse points matching by combining 3D mesh saliency with statistical descriptorsCOMPUTER GRAPHICS FORUM, Issue 2 2008U. Castellani Abstract This paper proposes new methodology for the detection and matching of salient points over several views of an object. The process is composed by three main phases. In the first step, detection is carried out by adopting a new perceptually-inspired 3D saliency measure. Such measure allows the detection of few sparse salient points that characterize distinctive portions of the surface. In the second step, a statistical learning approach is considered to describe salient points across different views. Each salient point is modelled by a Hidden Markov Model (HMM), which is trained in an unsupervised way by using contextual 3D neighborhood information, thus providing a robust and invariant point signature. Finally, in the third step, matching among points of different views is performed by evaluating a pairwise similarity measure among HMMs. An extensive and comparative experimental session has been carried out, considering real objects acquired by a 3D scanner from different points of view, where objects come from standard 3D databases. Results are promising, as the detection of salient points is reliable, and the matching is robust and accurate. [source] Microstructural, thermal, and electrical properties of Bi1.7V0.3Sr2Ca2Cu3Ox glass-ceramic superconductorCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2004T. S. Kayed Abstract A glass-ceramic Bi1.7V0.3Sr2Ca2Cu3Ox superconductor was prepared by the melt-quenching method. The compound was characterized by scanning electron microscopy, x-ray diffraction, differential thermal analysis, current-voltage characteristics, transport resistance measurements, and Hall effect measurements. Two main phases (BSCCO 2212 and 2223) were observed in the x-ray data and the values of the lattice parameters quite agree with the known values for 2212 and 2223 phases. The glass transition temperature was found to be 426 °C while the activation energy for crystallization of glass has been found to be Ea = 370.5 kJ / mol. This result indicates that the substitution of vanadium increased the activation energy for the BSCCO system. An offset Tc of 80 K was measured and the onset Tc was 100 K. The Hall resistivity ,H was found to be almost field-independent at the normal state. A negative Hall coefficient was observed and no sign reversal of ,H or RH could be noticed. The mobility and carrier density at different temperatures in the range 140-300 K under different applied magnetic fields up to 1.4 T were also measured and the results are discussed. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Assessment of the Tilting Properties of the Human Mitral Valve during Three Main Phases of the Heart Cycle: An Echocardiographic StudyECHOCARDIOGRAPHY, Issue 4 2006Daniel Vanhercke B.N., N.F.E.S.C., R.D.C.S. Rationale and Objectives: In experimental models of the left heart, the mitral valve (MV) is commonly implanted perpendicular to a central axis of the apex/MV. To adapt this to a more correct anatomical model, as well as for further studies of the left ventricle, we created a database of implantation angles of the MV and annulus during three main phases of the heart cycle, based on standard cardiac ultrasound measurements. Materials and Methods: Twenty-eight patients were studied with the standard cardiac ultrasound equipment. From the apical echo window, an anteroposterior (AP) plane and a perpendicular commisure-commisure (CC) plane were generated during three critical moments in the heart cycle: systole (S); diastole early filling (E); and diastole late filling (A). In both planes, the angles between the annular plane and each mitral leaflet, as well as the angle between a theoretical longitudinal axis through the apex and center of the MV orifice and the mitral annulus plane, were measured with a custom-made application of Matlab R14. Results: We observed an inclination of the angle mitral annulus/central left ventricle axis, with its lowest point in the direction of the aortic valve (AP plane) of 85°± 7° in systole (S), 88°± 8° in early diastole (E), and 88°± 7° in late diastole (A). In the CC plane, we observed an almost horizontal implantation of 91°± 5° in systole (S), 91°± 8° in early diastole (E), and 91°± 7° in late diastole (A). [source] Expression of Hoxa-11 and Hoxa-13 in the pectoral fin of a basal ray-finned fish, Polyodon spathula: implications for the origin of tetrapod limbsEVOLUTION AND DEVELOPMENT, Issue 3 2005Brian D. Metscher Summary Paleontological and anatomical evidence suggests that the autopodium (hand or foot) is a novel feature that distinguishes limbs from fins, while the upper and lower limb (stylopod and zeugopod) are homologous to parts of the sarcopterygian paired fins. In tetrapod limb development Hoxa-11 plays a key role in differentiating the lower limb and Hoxa-13 plays a key role in differentiating the autopodium. It is thus important to determine the ancestral functions of these genes in order to understand the developmental genetic changes that led to the origin of the tetrapod autopodium. In particular it is important to understand which features of gene expression are derived in tetrapods and which are ancestral in bony fishes. To address these questions we cloned and sequenced the Hoxa-11 and Hoxa-13 genes from the North American paddlefish, Polyodon spathula, a basal ray-finned fish that has a pectoral fin morphology resembling that of primitive bony fishes ancestral to the tetrapod lineage. Sequence analysis of these genes shows that they are not orthologous to the duplicated zebrafish and fugu genes. This implies that the paddlefish has not duplicated its HoxA cluster, unlike zebrafish and fugu. The expression of Hoxa-11 and Hoxa-13 in the pectoral fins shows two main phases: an early phase in which Hoxa-11 is expressed proximally and Hoxa-13 is expressed distally, and a later phase in which Hoxa-11 and Hoxa-13 broadly overlap in the distal mesenchyme of the fin bud but are absent in the proximal fin bud. Hence the distal polarity of Hoxa-13 expression seen in tetrapods is likely to be an ancestral feature of paired appendage development. The main difference in HoxA gene expression between fin and limb development is that in tetrapods (with the exception of newts) Hoxa-11 expression is suppressed by Hoxa-13 in the distal limb bud mesenchyme. There is, however, a short period of limb bud development where Hoxa-11 and Hoxa-13 overlap similarly to the late expression seen in zebrafish and paddlefish. We conclude that the early expression pattern in tetrapods is similar to that seen in late fin development and that the local exclusion by Hoxa-13 of Hoxa-11 from the distal limb bud is a derived feature of limb developmental regulation. [source] Stratigraphic and structural evolution of the Blue Nile Basin, Northwestern Ethiopian PlateauGEOLOGICAL JOURNAL, Issue 1 2009N. DS. Abstract The Blue Nile Basin, situated in the Northwestern Ethiopian Plateau, contains ,1400,m thick Mesozoic sedimentary section underlain by Neoproterozoic basement rocks and overlain by Early,Late Oligocene and Quaternary volcanic rocks. This study outlines the stratigraphic and structural evolution of the Blue Nile Basin based on field and remote sensing studies along the Gorge of the Nile. The Blue Nile Basin has evolved in three main phases: (1) pre-sedimentation phase, include pre-rift peneplanation of the Neoproterozoic basement rocks, possibly during Palaeozoic time; (2) sedimentation phase from Triassic to Early Cretaceous, including: (a) Triassic,Early Jurassic fluvial sedimentation (Lower Sandstone, ,300,m thick); (b) Early Jurassic marine transgression (glauconitic sandy mudstone, ,30,m thick); (c) Early,Middle Jurassic deepening of the basin (Lower Limestone, ,450,m thick); (d) desiccation of the basin and deposition of Early,Middle Jurassic gypsum; (e) Middle,Late Jurassic marine transgression (Upper Limestone, ,400,m thick); (f) Late Jurassic,Early Cretaceous basin-uplift and marine regression (alluvial/fluvial Upper Sandstone, ,280,m thick); (3) the post-sedimentation phase, including Early,Late Oligocene eruption of 500,2000,m thick Lower volcanic rocks, related to the Afar Mantle Plume and emplacement of ,300,m thick Quaternary Upper volcanic rocks. The Mesozoic to Cenozoic units were deposited during extension attributed to Triassic,Cretaceous NE,SW-directed extension related to the Mesozoic rifting of Gondwana. The Blue Nile Basin was formed as a NW-trending rift, within which much of the Mesozoic clastic and marine sediments were deposited. This was followed by Late Miocene NW,SE-directed extension related to the Main Ethiopian Rift that formed NE-trending faults, affecting Lower volcanic rocks and the upper part of the Mesozoic section. The region was subsequently affected by Quaternary E,W and NNE,SSW-directed extensions related to oblique opening of the Main Ethiopian Rift and development of E-trending transverse faults, as well as NE,SW-directed extension in southern Afar (related to northeastward separation of the Arabian Plate from the African Plate) and E,W-directed extensions in western Afar (related to the stepping of the Red Sea axis into Afar). These Quaternary stress regimes resulted in the development of N-, ESE- and NW-trending extensional structures within the Blue Nile Basin. Copyright © 2008 John Wiley & Sons, Ltd. [source] A deterministic seismic hazard map of India and adjacent areasGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2003Imtiyaz A. Parvez SUMMARY A seismic hazard map of the territory of India and adjacent areas has been prepared using a deterministic approach based on the computation of synthetic seismograms complete with all main phases. The input data set consists of structural models, seismogenic zones, focal mechanisms and earthquake catalogues. There are few probabilistic hazard maps available for the Indian subcontinent, however, this is the first study aimed at producing a deterministic seismic hazard map for the Indian region using realistic strong ground motion modelling with the knowledge of the physical process of earthquake generation, the level of seismicity and wave propagation in anelastic media. Synthetic seismograms at a frequency of 1 Hz have been generated at a regular grid of 0.2°× 0.2° by the modal summation technique. The seismic hazard, expressed in terms of maximum displacement (Dmax), maximum velocity (Vmax), and design ground acceleration (DGA), has been extracted from the synthetic signals and mapped on a regular grid over the studied territory. The estimated values of the peak ground acceleration are compared with the observed data available for the Himalayan region and are found to be in agreement. Many parts of the Himalayan region have DGA values exceeding 0.6 g. The epicentral areas of the great Assam earthquakes of 1897 and 1950 in northeast India represent the maximum hazard with DGA values reaching 1.2,1.3 g. The peak velocity and displacement in the same region is estimated as 120,177 cm s,1 and 60,90 cm, respectively. [source] Institutional Mergers in Australian Higher Educaiton since 1960HIGHER EDUCATION QUARTERLY, Issue 4 2000Grant Harman For the past forty years, institutional mergers have been a major and controversial theme in Australian higher education. Three main phases of major mergers are reviewed with particular attention being paid to reasons for merger, success factors, and longer term results. While merger experiences have often been traumatic for participants and participating institutions, on balance the longer term results have been positive, producing a university system today comprising relatively large and comprehensive institutions, well suited to compete in the new internationally competitive environment. [source] Prioritisation of public investments in social infrastructures using multicriteria value analysis and decision conferencing: a case studyINTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 4 2006Carlos A. Bana e Costa Abstract Not-for-profit private organisations that provide social services to children, the elderly and the disabled apply for financial support to develop or to renew their social infrastructures, through the Portuguese Institute for Social Welfare. In the context of scarce financial resources, the Institute decision-makers felt the need to adopt an improved "rationality" in resource allocation, in order to increase transparency and to ensure that the collective best use is made of a limited budget. This paper describes the socio-technical process followed in building a multicriteria value model, under a decision conferencing framework in which participation and interaction among decision-actors were key features in the development of the three main phases of problem structuring, evaluation and prioritisation. [source] The evolution of family interventions for schizophrenia.JOURNAL OF FAMILY THERAPY, Issue 1 2006A tribute to Gianfranco Cecchin Family intervention for schizophrenia has informed the whole history of family therapy, although in different fashions. This presentation will deal with the main phases of such intervention, outlining the characteristic features of each one. We can roughly divide the history of family intervention for schizophrenia into four phases: Phase 1 , Conjoint family therapy (1955,1965). Family interventions were aimed at modifying family communication patterns, implying the possibility of a definitive resolution of psychopathology. Phase 2 , Antipsychiatry (1965,1975). This, rather than a treatment model, was a philosophy of psychiatry, which considered schizophrenia as an epiphenomenon of the distortions of Western society. Family treatment was aimed at promoting the awareness of such a dynamic. Phase 3 , Milan systemic therapy (1975,1985). The systemic model was aimed at helping people with schizophrenia to recognize their position within their families (and other significant systems), giving all family members a new sense of their relationships to each other. Phase 4 , Psychoeducation (1985,2005). In most psychoeducational models, schizophrenia was conceived of as a biologically determined disorder. Psychoeducation was a way of helping the not diagnosed family members to cope with problems brought about by the illness, eliciting consensus towards psychiatric treatments such as medication and rehabilitation. A fifth phase of family intervention for schizophrenia is probably developing right now. If this is happening it should probably be an integrative phase, in which different approaches to family dynamics might be bridged and blended, in order to give more effective help to all members of families with schizophrenia. [source] Deformation-enhanced metamorphic reactions and the rheology of high-pressure shear zones, Western Gneiss Region, NorwayJOURNAL OF METAMORPHIC GEOLOGY, Issue 1 2006M. P. TERRY Abstract Microstructural and petrological analysis of samples with increasing strain in high-pressure (HP) shear zones from the Haram garnet corona gabbro give insights into the deformation mechanisms of minerals, rheological properties of the shear zone and the role of deformation in enhancing metamorphic reactions. Scanning electron microscopy with electron backscattering diffraction (SEM,EBSD), compositional mapping and petrographic analysis were used to evaluate the nature of deformation in both reactants and products associated with eclogitization. Plagioclase with a shape-preferred orientation that occurs in the interior part of layers in the mylonitic sample deformed by intracrystalline glide on the (0 0 1)[1 0 0] slip system. In omphacite, crystallographic preferred orientations indicate slip on (1 0 0)[0 0 1] and (1 1 0)[0 0 1] during deformation. Fine-grained garnet deformed by diffusion creep and grain-boundary sliding. Ilmenite deformed by dislocation glide on the basal and, at higher strains, prism planes in the a direction. Relationships among the minerals present and petrological analysis indicate that deformation and metamorphism in the shear zones began at 500,650 °C and 0.5,1.4 GPa and continued during prograde metamorphism to ultra-high-pressure (UHP) conditions. Both products and reactants show evidence of syn- and post-kinematic growth indicating that prograde reactions continued after strain was partitioned away. The restriction of post-kinematic growth to narrow regions at the interface of garnet and plagioclase and preservation of earlier syn-kinematic microstructures in older parts layers that were involved in reactions during deformation show that diffusion distances were significantly shortened when strain was partitioned away, demonstrating that deformation played an important role in enhancing metamorphic reactions. Two important consequences of deformation observed in these shear zones are: (i) the homogenization of chemical composition gradients occurred by mixing and grain-boundary migration and (ii) composition changes in zoned metamorphic garnet by lengthening diffusion distances. The application of experimental flow laws to the main phases present in nearly monomineralic layers yield upper limits for stresses of 100,150 MPa and lower limits for strain rates of 10,12 to 10,13 s,1 as deformation conditions for the shear zones in the Haram gabbro that were produced during subduction of the Baltica craton and resulted in the production of HP and UHP metamorphic rocks. [source] The role of Raman microspectroscopy in the study of black gloss coatings on Roman potteryJOURNAL OF RAMAN SPECTROSCOPY, Issue 1 2005Francesca Ospitali Abstract Raman microspectroscopy was adopted for the study of black gloss coatings on Roman pottery, found in Rimini (northern Italy) and in Suasa, near Ancona (central Italy), dated second century B.C. This non-destructive technique allowed a very accurate analysis of the crystalline and amorphous components of thin surface layers. The investigated coating is black, homogeneous and glazed, without any crystals, becoming red on approaching to the ceramic body. Magnetite and carbon are the main phases of the black zones, whereas hercynite, quartz, silicates and haematite are the secondary components. In the red zones, approaching the ceramic body, the amount of haematite increases and the amount of magnetite decreases. The presence of carbon, on the surface only, confirms the hypothesis of a firing cycle in a partial reducing atmosphere. Copyright © 2004 John Wiley & Sons, Ltd. [source] Evolution of the Minangkabau's shifting cultivation in the West Sumatra highland OF Indonesia and its strategic implications for dynamic farming systemsLAND DEGRADATION AND DEVELOPMENT, Issue 1 2005A. Dendi Abstract This paper explores the evolution of the shifting cultivation of the Minangkabau, the biggest matrilineal society in Indonesia, and examines factors underlying the instability and vulnerability of farmers' livelihoods and the degradation of their resource base using an extended factor analysis technique, in order to understand how development strategies might be modified towards a more dynamic farming system. The study distinguished three main phases of the farming system's changes and found that these changes highly corresponded with the emerging market and institutional incentives. Furthermore, the factor analysis generated a six-factor model suggesting strategic interventions to foster the improvement of farmers' livelihoods and environment in future. In addition, consistent with the results of these factors analysis, we argue that, provided land tenure is conducive, there are substantial possibilities for policies and interventions that focus first on agricultural diversification and then on organization building, to assist in dealing with farmers' vulnerability and environmental degradation in the uplands. Copyright © 2004 John Wiley & Sons, Ltd. [source] Coagulation of Carboxylic Acid-Functionalized LatexesMACROMOLECULAR SYMPOSIA, Issue 1 2008Adélia Santos Abstract In the present work, the stability of particles produced by emulsion polymerization and stabilized by carboxylic acid groups was studied from turbidity measurements. To achieve this, a number of copolymerization runs was carried out under different reaction conditions, including the use of different carboxylic monomers. Partitioning analyses using conductimetric and potentiometric titrations were performed in order to assess the distribution of carboxylic monomers among the main phases of the produced latexes. Additionally, the stability and coalescence of particles were measured by turbidimetry in a diluted latex considering either the presence or not of the anionic surfactant sodium lauryl sulfate. Coalescence of particles was provoked in the latex samples at different temperatures by addition of an aliquot of a concentrated solution of electrolyte. The influence of surfactant, temperature and type of carboxylic acid group on the particle stability was investigated. [source] Forming supermassive black holes by accreting dark and baryon matterMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2006Jian Hu ABSTRACT Given a large-scale mixture of self-interacting dark matter (SIDM) particles and baryon matter distributed in the early Universe, we advance here a two-phase accretion scenario for forming supermassive black holes (SMBHs) with masses around ,109 M, at high redshifts z(,6). The first phase is conceived to involve a rapid quasi-spherical and quasi-steady Bondi accretion of mainly SIDM particles embedded with baryon matter on to seed black holes (BHs) created at redshifts z, 30 by the first generation of massive Population III stars; this earlier phase rapidly gives birth to significantly enlarged seed BH masses of during z, 20,15, where ,0 is the cross-section per unit mass of SIDM particles and Cs is the velocity dispersion in the SIDM halo referred to as an effective ,sound speed'. The second phase of BH mass growth is envisaged to proceed primarily via baryon accretion, eventually leading to SMBH masses of MBH, 109 M,; such SMBHs may form either by z, 6 for a sustained accretion at the Eddington limit or later at lower z for sub-Eddington mean accretion rates. In between these two phases, there is a transitional yet sustained diffusively limited accretion of SIDM particles which in an eventual steady state would be much lower than the accretion rates of the two main phases. We intend to account for the reported detections of a few SMBHs at early epochs, e.g. Sloan Digital Sky Survey (SDSS) 1148+5251 and so forth, without necessarily resorting to either super-Eddington baryon accretion or very frequent BH merging processes. Only extremely massive dark SIDM haloes associated with rare peaks of density fluctuations in the early Universe may harbour such early SMBHs or quasars. Observational consequences are discussed. During the final stage of accumulating a SMBH mass, violent feedback in circumnuclear environs of a galactic nucleus leads to the central bulge formation and gives rise to the familiar empirical MBH,,b correlation inferred for nearby normal galaxies with ,b being the stellar velocity dispersion in the galactic bulge; in our scenario, the central SMBH formation precedes that of the galactic bulge. [source] Carlin-type Gold Prospects in Surigao del Norte, Mindanao Island, Philippines: Their Geology and Mineralization PotentialRESOURCE GEOLOGY, Issue 3 2005Victor B. Maglambayan Abstract. Three calcareous sedimentary rock-hosted Carlin type-like gold prospects were mapped in a mineral production sharing agreement area of Philex Gold Philippines Inc. in Taganaan municipality, Surigao del Norte province in Mindanao island in the Philippines. They occur along a 20,25 km long trend of known epigenetic gold and porphyry copper deposits that lie close to several splays of the Philippine Fault Zone. The gold district forms part of the Late Cretaceous Eastern Mindanao Range that hosts early Paleogene and late Pliocene to Quaternary intrusive rocks. Gold is invisible in the jasperoid outcrops in Lascogon, Napo, and Danao prospects. The jasperoids occur in lenses of marls belonging to the Taganaan Marl Member that is associated to a turbiditic member of the Middle Miocene Mabuhay Formation. The marl lenses include gently dipping interbedded silty limestones and calcareous shales. The "invisible gold" mineralization in silicified calcareous rocks resembles Carlin-type deposits. Based on the mapped igneous and sedimentary rocks, a possible heat source for the gold mineralization is either or both of the two main phases of intrusion, Mabuhay An-desite or Alipao Andesite Porphyry. Forty-eight rock samples, fifteen stream sediment samples, and one soil sample were critical in delineating the general features of the potential Carlin-type prospects. The gold grades of jasperoids in the three prospects range from trace amounts to 20 g/t Au. Regional studies of gold and porphyry copper mineralization in the Surigao del Norte mineral district are important in delineating ore targets for drilling in the three prospects. [source] EVALUATING EU POLICIES ON PUBLIC SERVICES: A CITIZENS' PERSPECTIVEANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 2 2010Judith Clifton ABSTRACT,:,This article evaluates EU policies on public services , particularly public network services , from the citizens' point of view. It is first argued that citizens' perceptions are important because the provision of fundamental services is at stake and because they constitute the infrastructure necessary for social and economic development. Citizens',voice' can, therefore, be known, analyzed and used in the design of improved policy on public services along with other indicators. Changing EU policy on public services is synthesized and classified into two main phases in section two. Citizen satisfaction with public services as revealed through surveys from 1997 to 2007 is explored in the third section. In the discussion, the prospects for EU policy on public services are considered and, it is argued that, from the perspectives of subsidiarity and proportionality, policy towards strengthening the common market is being increasingly uploaded to the supranational level in the form of directives, whilst cohesion and redistribution policies are being downloaded to the national level or dealt with at the supranational level by ,soft' instruments. [source] Character of the Si and Al Phases in Coal Gangue and Its AshACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 6 2009WANG Lihua Abstract: Analysis of the Si and Al phases in coal gangue fuel and its ash is important for use of coal gangue ashes. A comprehensive study by theoretical and experimental analyses with differential thermal analysis, X-ray diffraction and Infrared Spectroscopy has been made in the present article to explore the diagram of the Si and Al phases in coal gangue fuel and its ashes. It is found that kaolinite and quartz are the main phases in coal gangue fuel. The ratio of moles Al2O3to SiO2 (i.e., Al2O3 (mole)/ SiO2 (mole)) is usually no more than 0.5 in most coal gangue fuel and its ashes. The kaolinit at about 984°C releases a large quantity of SiO2, which makes calcine coal gangue more active than coal gangue itself. The relationship between the ratio Al2O3 (mole)/SiO2 (mole) and the components of coal gangue ash is analyzed, resulting in a formula to calculate the quantity of each phase. Applying the formula to the testing samples from an electric plant in north China supports the above conclusions. [source] | |||||||||||||||||||||||||||||||