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Main Stages (main + stage)
Selected AbstractsGeneration and accumulation of oil and condensates in the Wenchang A Sag, western Pearl River Mouth Basin, South China SeaGEOFLUIDS (ELECTRONIC), Issue 4 2009H. J. GAN Abstract The Pearl River Mouth (PRM) Basin is one of four Cenozoic basins in the South China Sea, and the Wenchang A Sag is a secondary depression in the western part of the basin. Both the Wenchang and Enping formations contain good source rocks in the western PRM Basin; however, only the latter has been considered a likely source of the discovered oil and gas. New data from fluid inclusions and the analysis of oil,source rock correlations for the WC10-3 oil and gas pools indicate two stages of petroleum charging, the earlier originating from the Wenchang Formation and the later from the Enping Formation. Kinetics of petroleum generation and structural evolution modeling were employed to further investigate the mechanism of formation of the WC10-3 oil and gas pools. It was shown that the crucial condition for the formation of pools is the time of development of the structural trap. The Wenchang Formation source rocks generated oil from 25 to 14 Ma in the possible source area of the WC10-3 oil and gas pools in the Wenchang A Sag, so that only traps formed earlier than this period could capture oil sourced by the Wenchang Formation. The Enping Formation source rock experienced its oil window from 18 Ma to the present with the main stage of oil generation from 15 to 5 Ma. During this period structural traps in the sag continued to form until movements became weak, so that most pools in the Wenchang A Sag originated from the Enping Formation source rock. The likely dissipation of oil and gas from the earlier stage of charging should be taken into account in assessing the oil potential of the Wenchang A Sag. [source] Ultrahigh-pressure metamorphism and exhumation of garnet peridotite in Pohorje, Eastern AlpsJOURNAL OF METAMORPHIC GEOLOGY, Issue 1 2006M. JANÁK Abstract New evidence for ultrahigh-pressure metamorphism (UHPM) in the Eastern Alps is reported from garnet-bearing ultramafic rocks from the Pohorje Mountains in Slovenia. The garnet peridotites are closely associated with UHP kyanite eclogites. These rocks belong to the Lower Central Austroalpine basement unit of the Eastern Alps, exposed in the proximity of the Periadriatic fault. Ultramafic rocks have experienced a complex metamorphic history. On the basis of petrochemical data, garnet peridotites could have been derived from depleted mantle rocks that were subsequently metasomatized by melts and/or fluids either in the plagioclase-peridotite or the spinel-peridotite field. At least four stages of recrystallization have been identified in the garnet peridotites based on an analysis of reaction textures and mineral compositions. Stage I was most probably a spinel peridotite stage, as inferred from the presence of chromian spinel and aluminous pyroxenes. Stage II is a UHPM stage defined by the assemblage garnet + olivine + low-Al orthopyroxene + clinopyroxene + Cr-spinel. Garnet formed as exsolutions from clinopyroxene, coronas around Cr-spinel, and porphyroblasts. Stage III is a decompression stage, manifested by the formation of kelyphitic rims of high-Al orthopyroxene, aluminous spinel, diopside and pargasitic hornblende replacing garnet. Stage IV is represented by the formation of tremolitic amphibole, chlorite, serpentine and talc. Geothermobarometric calculations using (i) garnet-olivine and garnet-orthopyroxene Fe-Mg exchange thermometers and (ii) the Al-in-orthopyroxene barometer indicate that the peak of metamorphism (stage II) occurred at conditions of around 900 °C and 4 GPa. These results suggest that garnet peridotites in the Pohorje Mountains experienced UHPM during the Cretaceous orogeny. We propose that UHPM resulted from deep subduction of continental crust, which incorporated mantle peridotites from the upper plate, in an intracontinental subduction zone. Sinking of the overlying mantle and lower crustal wedge into the asthenosphere (slab extraction) caused the main stage of unroofing of the UHP rocks during the Upper Cretaceous. Final exhumation was achieved by Miocene extensional core complex formation. [source] Vertical extrusion and middle crustal spreading of omphacite granulite: a model of syn-convergent exhumation (Bohemian Massif, Czech Republic)JOURNAL OF METAMORPHIC GEOLOGY, Issue 3 2004típská Abstract The exhumation of eclogite facies granulites (Omp,Plg,Grt,Qtz,Rt) in the Rychleby Mts, eastern Czech Republic, was a localised process initiated by buckling of crustal layers in a thickened orogenic root. Folding and post-buckle flattening was followed by the main stage of exhumation that is characterized by vertical ductile extrusion. This process is documented by structural data, and the vertical ascent of rocks from a depth of c. 70 to c. 35 km is documented by metamorphic petrology. SHRIMP 206Pb/238U and 207Pb/206Pb evaporation zircon ages of 342 ± 5 and 341.4 ± 0.7 Ma date peak metamorphic conditions. The next stage of exhumation was associated with sideways flat thrusting associated with lateral viscous spreading of granulites and surrounding rocks over indenting adjacent continental crust at a depth of c. 35,30 km. This stage was associated with syntectonic intrusion of a granodiorite sill at 345,339 Ma, emplaced at a crustal depth of c. 25 km. The time required for cooling of the sill as well as for heating of the country rocks brackets this event to a maximum of 250 000 years. Therefore, similar ages of crystallization for the granodiorite magma and the peak of eclogite facies metamorphism of the granulite suggest a very short period of exhumation, limited by the analytical errors of the dating methods. Our calculations suggest that the initial exhumation rate during vertical extrusion was 3,15 mm yr,1, followed by an exhumation rate of 24,40 mm yr,1 during further uplift along a magma-lubricated shear zone. The extrusion stage of exhumation was associated with a high cooling rate, which decreased during the stage of lateral spreading. [source] BURIAL HISTORY RECONSTRUCTION USING LATE DIAGENETIC PRODUCTS IN THE EARLY PERMIAN SILICICLASTICS OF THE FARAGHAN FORMATION, SOUTHERN ZAGROS, IRANJOURNAL OF PETROLEUM GEOLOGY, Issue 2 2009S. M. Zamanzadeh In spite of the increasing importance to hydrocarbon exploration and production of the Palaeozoic succession in the Zagros area of SW Iran, few burial history and palaeothermal modelling studies of the interval have been carried out. This paper attempts to assess the burial and palaeotemperature history of the Lower Permian Faraghan Formation which is composed of stromatolitic dolomites overlain by mainly cross-bedded sandstones. The formation grades up into the thick bedded carbonates of the Upper Permian Dalan Formation. The Faraghan and Dalan Formations are major hydrocarbon reservoir units in SW Iran and are time-equivalents of the Unayzah and Khuff Formations in Saudi Arabia, respectively. The Faraghan Formation consists of shallow-marine siliciclastics and foreshore deposits, including tidal-flat and tidal-channel, estuarine, sabkha, shoreface and offshore facies. In this study, diagenetic constituents are used to evaluate the formation's burial history in the Southern Zagros, an area for which only limited subsurface data is available. A burial history diagram for the formation was constructed for well Finu # 1 using WinBuryTM software. The diagram shows that the formation underwent progressive burial at variable rates between its deposition and the mid-Tertiary, since when it has undergone rapid uplift. Burial diagenetic products in the Faraghan Formation comprise saddle, ferroan and zoned dolomites, together with dickite, illite/sericite and chlorite minerals. Additional burial-related features include stylolites and dissolution seams. Isotopic signatures (,18O versus ,13C) of the ferroan dolomites suggest a burial trend for the formation. Reconstruction of the paragenetic sequence together with the burial history diagram suggests a maximum burial depth of about 5000 m and a wide palaeotemperature range of 80-160°C. However considering the saddle dolomites as a palaeothermometer, the temperature range narrows to 78 to 138 °C. The burial depth and temperature ranges closely correlate with the main stage of oil generation to the dry gas zone. [source] Epithermal Gold-Silver Mineralization of the Asachinskoe Deposit in South Kamchatka, RussiaRESOURCE GEOLOGY, Issue 4 2007Ryohei Takahashi Abstract The Asachinskoe epithermal Au-Ag deposit is a representative low-sulfidation type of deposit in Kamchatka, Russia. In the Asachinskoe deposit there are approximately 40 mineralized veins mainly hosted by dacite,andesite stock intrusions of Miocene,Pliocene age. The veins are emplaced in tensional cracks with a north orientation. Wall-rock alteration at the bonanza level (170,200 m a.s.l.) consists of the mineral assemblage of quartz, pyrite, albite, illite and trace amounts of smectite. Mineralized veins are well banded with quartz, adularia and minor illite. Mineralization stages in the main zone are divided into stages I,IV. Stage I is relatively barren quartz,adularia association formed at 4.7 ± 0.2 Ma (K-Ar age). Stage II consists of abundant illite, Cu-bearing cryptomelane and other manganese oxides and hydroxides, electrum, argentite, quartz, adularia and minor rhodochrosite and calcite. Stage III, the main stage of gold mineralization (4.5,4.4 ± 0.1,3.1 ± 0.1 Ma, K-Ar age), consists of a large amount of electrum, naumannite and Se-bearing polybasite with quartz,adularia association. Stage IV is characterized by hydrothermal breccia, where electrum, tetrahedrite and secondary covellite occur with quartz, adularia and illite. The concentration of Au+Ag in ores has a positive correlation with the content of K2O + Al2O3, which is controlled by the presence of adularia and minor illite, and both Hg and Au also have positive correlations with the light rare-earth elements. Fluid inclusion studies indicate a salinity of 1.0,2.6 wt% NaCl equivalent for the whole deposit, and ore-forming temperatures are estimated as approximately 160,190°C in stage III of the present 218 m a.s.l. and 170,180°C in stage IV of 200 m a.s.l. The depth of ore formation is estimated to be 90,400 m from the paleo-water table for stage IV of 200 m a.s.l., if a hydrostatic condition is assumed. An increase of salinity (>CNaCl, 0.2 wt%) and decrease of temperature (>T , 30°C) within a 115-m vertical interval for the ascending hydrothermal solution is calculated, which is interpreted as due to steam loss during fluid boiling. Ranges of selenium and sulfur fugacities are estimated to be logfSe2 = ,17 to ,14.5 and logfS2 = ,15 to ,12 for the ore-forming solution that was responsible for Au-Ag-Se precipitation in stage III of 200 m a.s.l. Separation of Se from S-Se complex in the solution and its partition into selenides could be due to a relatively oxidizing condition. The precipitation of Au-Ag-Se was caused by boiling in stage III, and the precipitation of Au-Ag-Cu was caused by sudden decompression and boiling in stage IV. [source] Yerranderie a Late Devonian Silver,Gold,Lead Intermediate Sulfidation Epithermal District, Eastern Lachlan Orogen, New South Wales, AustraliaRESOURCE GEOLOGY, Issue 1 2007Peter M. Downes Abstract Felsic volcanic units of the Early Devonian Bindook Volcanic Complex host the Yerranderie epithermal silver,gold,lead district 94 km west,southwest of Sydney. Mineralization in the district forms part of a fault-controlled, intermediate sulfidation, epithermal silver,gold,base metal vein system that has significant mineral and alteration zonation. Stage 1 of the mineral paragenesis in the veins developed quartz and carbonate with early pyrite, whereas stage 2 is a crustiform banded quartz,pyrite,arsenopyrite assemblage. Stage 3, the main stage of sulfide deposition, comprises early sphalerite, followed by a tetrahedrite,tennantite,gold assemblage, then a galena,chalcopyrite,native silver,pyrite assemblage, and finally a pyrargyrite,polybasite,pearceite assemblage. Stage 4 involves the deposition of quartz veins with minor (late) pyrite and stage 5 is characterized by siderite that infilled remaining voids. Mineral zonation occurs along the Yerranderie Fault, with bornite being restricted to the Colon Peaks,Silver Peak mine area, whereas arsenopyrite, which is present in both the Colon Peaks,Silver Peak and Wollondilly mine areas, is absent in other lodes along the Yerranderie Fault. The Yerranderie Fault, which hosts the major lodes, is surrounded by a zoned alteration system. With increasing proximity to the fault the intensity of alteration increases and the alteration assemblage changes from an outer quartz,muscovite,illite,(ankerite) assemblage to a quartz,illite,(pyrite,carbonate) assemblage within meters of the fault. 40Ar/39Ar dating of muscovite from the alteration zone gave a 372.1 ± 1.9 Ma (Late Devonian) age, which is interpreted to be the timing of the quartz,sulfide vein formation. Sulfur isotope values for sulfides range from 0.1 to 6.2, with one outlier of ,5.6 ,34S,. The results indicate that the initial ore-forming fluids were reduced, and that sulfur was probably sourced from a magmatic reservoir, either as a direct magmatic contribution or indirectly through dissolution and recycling of sulfur from the host volcanic sequence. The sulfur isotope data suggest the system is isotopically zoned. [source] Hydrothermal Fluid Evolution Associated with Gold Mineralization at the Wenyu Mine, Xiaoqinling District, ChinaRESOURCE GEOLOGY, Issue 2 2000Neng JIANG Abstract: The Wenyu mesothermal gold deposit is located in the Xiaoqinling district about 1000 km southwest of Beijing in central China. It occurs in the Late Archean to Early Proterozoic metamorphosed volcanic and sedimentary rocks. Three distinct stages of veins have been identified: (I) gold-poor quartz,pyrite veins, (II) gold-rich sulfide,quartz veins, and (III) gold-poor carbonate,quartz veins. Stage II can be subdivided into IIa and IIb. Gold typically occurs as fracture-fillings associated with chalcopyrite and galena. Fluid inclusions were examined in quartz samples from veins of both stage I and II. Three types of fluid inclusions are identified: CO2,H2O, CO2,rich, and aqueous inclusions. The first two types are of primary in origin. The last type occurs in two ways: coexisting with CO2,H2O and CO2,rich inclusions and thus primary in origin; and occurring along late healed fractures and hence secondary in origin. CO2,H2O inclusions display progressively decreasing Th and increasing Thco2, from the highest Th (311,408C) and lowest Thco2 (average 18C) in stage I quartz through middle Th (284,358C) and ThCO2(average 25C) in stage IIa quartz to the lowest Th (275,314C) and highest ThCO2 (average 28C) in stage IIb quartz, indicating an evolving H2O,CO2,NaCl fluid system. CO2,rich and primary aqueous inclusions show consistent ThCO2 or Th with their coexistent CO2,H2O inclusions. Whereas the secondary aqueous inclusions in stage I and IIa quartz have almost the same Th and salinity as the primary aqueous inclusions in stage IIb quartz. Comparing with CO2,H2O inclusions, these non,CO2, low salinity aqueous inclusions may come from different origin, most probably meteoric water. Unlike in both stage I and IIa quartz, fluid inclusions in stage IIb do not show evidence of fluid immiscibility. The fact that most of gold is associated with stage IIa and IIb veins and not with veins of stage I which is the main stage of vein formation suggests that gold deposition occurs at the later stage of fluid immiscibility. The continuing phase separation led to the deposition of large amounts of gold at the Wenyu mine. [source] Faculty development for problem-based learningEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 2 2004Elizabeth A. Farmer Changing to a problem-based learning (PBL) curriculum represents a substantial challenge because many faculty members are unfamiliar with the process. Faculty development is a crucial component of successful curriculum change to PBL. This paper describes a logical process for designing and implementing a comprehensive faculty development programme at three main stages of change: curriculum transition, curriculum implementation and curriculum advancement. The components of each stage are discussed with reference to the literature and practice. Future advances in faculty development include harnessing the potential of complex adaptive systems theory in understanding and facilitating the change process, and incorporating the results of research, which illuminates the relationships of the PBL tutorial process to student achievement. There is a continuing need for rigorous outcome-based research and programme evaluation to define the best components and strategies for faculty development. [source] The historic man-made soils of the Generalife garden (La Alhambra, Granada, Spain)EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 1 2007R. Delgado Summary We studied the soils of the Patio de la Acequia garden of the Generalife, a palatial villa forming part of La Alhambra, a World Heritage Site in Granada, Spain. This garden, which is estimated to be around 700 years old, is the oldest historical garden in the Western World. The soils are man-made cumulimollihumic-calcaric (hypereutric, anthric) Regosols. Noteworthy amongst the main pedogenic processes, in relation to the human activities of cultivation, irrigation and tillage, are horizonation, melanization (the contents of organic carbon varied between 0.59% and 8.87%, and those of P205 extracted with citric acid between 723 mg kg,1 and 7333 mg kg,1, with maximae in the Ap horizons) and structure formation. The soil fabric, studied at the ultramicroscopic level using scanning electron microscopy, is of laminar and partition-walls' type in the lower horizons, depending on the microped zones. The partition-walls' fabrics found are different to those of the possible pre-existing sedimentary fabrics. These are numerous lithological discontinuities and at least two burials, leading us to deduce that there have been two main stages of filling with materials in the formation of these soils. The first is Arabic-Medieval (13th century), when the garden was created, its surface being some 50 cm below the level of the paved area of the present patio. In the deeper parts, the materials employed in the fill are similar to the in situ soils of the zone, unaffected by the buildings. The second stage is Christian (15th century to the present day). During this period the Medieval garden was gradually buried under a layer of materials from the nearby soils and/or sediments mixed with manure until the surface was only just below the level of the paved area of the patio. In this work we discuss the difficult classification of these relatively little studied soils. In spite of their being clearly related to human activity, they are not classified as Anthrosols in the FAO system (1998) because soil materials cannot be classified as anthropopedogenic or as anthropogeomorphic. [source] Refined spreading history at the Southwest Indian Ridge for the last 96 Ma, with the aid of satellite gravity dataGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 3 2005A. Bernard SUMMARY The spreading history of the oceans is modelled mostly by using magnetic anomalies and the fracture zone geometry. The high-quality, satellite-derived gravity data, that became available in recent years, reveal the details of fracture zones, which can be used as flow lines to control spreading models. We have applied this approach to the Southwest Indian Ridge (SWIR) in order to refine its spreading history. This is particularly useful for the period of complex spreading between magnetic anomalies 33 and 23, where the magnetic anomalies alone cannot resolve the detailed spreading history. We find four main stages in the spreading history of the SWIR since 96 Ma, including two that were not noted previously, between 96 Ma and anomaly 33 (76.3 Ma) and between anomalies 23o (51.7 Ma) and 18o (40.1 Ma; o denotes old boundaries of normal magnetization period). We also find that the start of the period of complex spreading was at anomaly 33, somewhat earlier than previously proposed. We discuss the characteristics of the extension that the old transform faults underwent during the complex spreading phase, in response to the counterclockwise rotation of spreading. New transform faults appeared at that time, considerably widening the transform zones. [source] Developing evidence-based recommendations in public health , incorporating the views of practitioners, service users and user representativesHEALTH EXPECTATIONS, Issue 1 2008Mary J Renfrew Abstract Background Guidance based on a systematic assessment of the evidence base has become a fundamental tool in the cycle of evidence-based practice and policy internationally. The process of moving from the formal evidence base derived from research studies to the formation and agreement of recommendations is however acknowledged to be problematic, especially in public health; and the involvement of practitioners, service commissioners and service users in that process is both important and methodologically challenging. Aim To test a structured process of developing evidence-based recommendations in public health while involving a broad constituency of practitioners, service commissioners and service user representatives. Methods As part of the development of national public health recommendations to promote and support breastfeeding in England, the methodological challenges of involving stakeholders were examined and addressed. There were three main stages: (i) an assessment of the formal evidence base (210 studies graded); (ii) electronic and fieldwork-based consultation with practitioners, service commissioners and service user representatives (563 participants), and an in-depth analytical consultation in three ,diagonal slice' workshops (89 participants); (iii) synthesis of the previous two stages. Results and conclusions The process resulted in widely agreed recommendations together with suggestions for implementation. It was very positively evaluated by participants and those likely to use the recommendations. Service users had a strong voice throughout and participated actively. This mix of methods allowed a transparent, accountable process for formulating recommendations based on scientific, theoretical, practical and expert evidence, with the added potential to enhance implementation. [source] Elastoplastic multiphase model for simulating the response of piled raft foundations subject to combined loadingsINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 9 2006G. Hassen Abstract A multiphase model and corresponding computational time-saving finite element code is proposed in this paper for predicting the settlements experienced by a piled raft foundation when subject to the combined action of vertical and lateral loadings. This model, which is formulated in the framework of an elastoplastic behaviour for the soil and the reinforcing piles as well, explicitly accounts for the shear and flexural behaviour of the latter. Starting from a simple analytical example where all the concepts attached to this model are clearly illustrated, the main stages leading to its finite element implementation are then presented. The numerical tool thus elaborated, is applied to the simulation of a pile-reinforced strip foundation submitted to a horizontally applied seismic load in addition to a permanent vertical load. One of the key results of such a simulation in terms of design recommendation, lies in the conclusion that, while the shear and flexural contributions of the reinforcement play quite a negligible role in the case of a vertical load (as compared with their axial resistance), they remain absolutely essential for withstanding the seismic lateral loading. Copyright © 2006 John Wiley & Sons, Ltd. [source] Development of nursing research in Germany in the European contextINTERNATIONAL JOURNAL OF NURSING PRACTICE, Issue 5 2000Mathilde Hackmann Rn MSc (Nsg & Ed) The development of nursing research in Germany is described in this article; in the first part, the evolution of nursing research in Europe is discussed briefly, then the development of nursing research in Germany is analysed using the framework of the main stages of the development of nursing research described by Tierney. A comparison of the differences between European and German development follows. Reasons for the differences are briefly analysed and discussed in the context of the German political and social background. [source] Evolution of M1 crown size and cusp proportions in the genus HomoJOURNAL OF ANATOMY, Issue 5 2009Rolf Quam Abstract Previous research into tooth crown dimensions and cusp proportions has proved to be a useful way to identify taxonomic differences in Pliocene and Pleistocene fossil hominins. The present study has identified changes in both M1 crown size and cusp proportions within the genus Homo, with M1 overall crown size reduction apparently occurring in two main stages. The first stage (a reduction of ca. 17%) is associated with the emergence of Homo ergaster and Homo erectus sensu stricto. The second stage (a reduction of ca. 10%) occurs in Homo sapiens, but the reduced modern human M1 tooth crown size was only attained in Upper Paleolithic times. The absolute sizes of the individual cusps are highly positively correlated with overall crown size and dental reduction produces a reduction in the absolute size of each of the cusps. Most of the individual cusps scale isometrically with crown size, but the paracone shows a negative allometric relationship, indicating that the reduction in paracone size is less than in the other M1 cusps. Thus, the phylogenetically oldest cusp in the upper molars also seems to be the most stable cusp (at least in the M1). The most striking change in M1 cusp proportions is a change in the relative size of the areas of the paracone and metacone. The combination of a small relative paracone and a large relative metacone generally characterizes specimens attributed to early Homo, and the presence of this character state in Australopithecus and Paranthropus suggests it may represent the primitive condition for the later part of the hominin clade. In contrast, nearly all later Homo taxa, with the exception of Homo antecessor, show the opposite condition (i.e. a relatively large paracone and a relatively small metacone). This change in the relationship between the relative sizes of the paracone and metacone is related to an isometric reduction of the absolute size of the metacone. This metacone reduction occurs in the context of relative stability in the paracone as crown size decreases. Among later Homo taxa, both Homo heidelbergensis and Homo neanderthalensis show a further reduction of the metacone and an enlargement of the hypocone. Fossil and contemporary H. sapiens samples show a trend toward increasing the relative size of the protocone and decreasing the relative size of the hypocone. In Europe, modern human M1 cusp proportions are essentially reached during the Upper Paleolithic. Although some variation was documented among the fossil taxa, we suggest that the relative size of the M1 paracone and metacone areas may be useful for differentiating the earliest members of our genus from subsequent Homo species. [source] Immigration and femininity in Southern Europe: A gender-based psychosocial analysisJOURNAL OF COMMUNITY & APPLIED SOCIAL PSYCHOLOGY, Issue 5 2008J. M. González-González Abstract Despite the growing presence of female immigrants in Western countries, research on the subject highlights two important biases that hinder appropriate explanation of the migratory phenomenon and hence prevent adequate intervention. First, most of the research studies conducted so far focus on male migration; second, the macro-social perspective has prevailed in these areas of study since socio-economic and political aspects have taken centre stage in analyses on migratory phenomena, From a gender-based psychosocial perspective, this study addresses the migration project of 53 women from different South American countries, the Maghreb region and Eastern Europe now living in Southern Spain. For this purpose we conducted 23 in-depth interviews, and staged six discussion groups with the aim of elucidating to what extent gender-based psychosocial beliefs,stereotypes, ideology and identity,determine women's migration process. Our results suggest that the main stages in the process,deciding to emigrate, itinerary for social and labour integration in the host country, and general assessment of the migration experience,are strongly influenced by psychosociological constructs which arise as a result of female gender-typing or female profile. Copyright © 2008 John Wiley & Sons, Ltd. [source] DETERMINATION OF pH CHANGE KINETICS DURING DIFFERENT STAGES OF KASHAR CHEESE MANUFACTURING FROM RAW AND PASTEURIZED MILK WITH ADDITION OF THERMOPHILIC, MESOPHILIC AND MIXED THERMOPHILIC CULTUREJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2008AHMET FERIT ATASOY ABSTRACT The pH change kinetics during Kashar cheese production from raw and pasteurized milk with addition of thermophilic, mesophilic and mixed thermophilic-mesophilic lactic acid bacteria were evaluated. The kinetics of pH change were determined during milk ripening, cooking/holding and pressing/fermentation phases of Kashar cheese. The pH decreased logarithmically, nonlinearly, with time in the milk ripening period, and reduced linearly with time in the cooking/holding and pressing/fermentation stages. Pasteurization of milk retarded the rate of change in pH during the three periods. The highest rate of pH change was determined in the addition of thermophilic culture, followed by mixed thermophilic-mesophilic and then mesophilic ones during milk ripening. The pH change characteristics of cheese made with thermophilic starter were similar to the cheese made with mixed thermophilic-mesophilic culture, but different from mesophilic lactic acid bacteria during cooking/holding and pressing/fermentation stages. PRACTICAL APPLICATIONS One of the important factors in the control of cheese quality is the extent of acid production in the vat. Acid development at a desired rate is important during cheese making. The progress of acidification is monitored by pH change in the industrial Kashar cheese production. Three main stages have been recognized with respect to pH change: milk ripening, cooking/holding and pressing/fermentation. This study evaluated and compared the pH change kinetics during various stages of Kashar cheese making using raw, pasteurized milk with the addition of thermophilic, mesophilic and mixed thermophilic culture. This work may help in the comparison of raw and pasteurized milk, and in the selection of appropriate starter culture for Kashar cheese production. [source] Poster Sessions AP01: Gene Expression and RegulationJOURNAL OF NEUROCHEMISTRY, Issue 2001J. M. Calandria The formation of Cortico-Thalamic projections requires the precise spatial and temporal expression of proteins that are involved in the different stages of synaptogenesis. We reasoned that the underlying molecular mechanism of this process is the differential expression of genes that code for stage specific proteins. Our research objective was to identify the differential expressed mRNAs during the main stages of synapses formation, which starts at embryonic day 12 (E12) and finishes on the first postnatal days in the rat. We approach this problem using Differential Display technique on three distinct ages of rat cerebral cortex that were: E13, E18 and postnatal day 0 (P0). We found 80 differential bands using 54 random primers and 18 of them were cloned and sequenced. The sequence analysis showed among others, a cDNA fragment highly homologous with the human A Kinase Anchoring Protein 450/350 also called CG-NAP. We found that this cDNA fragment homologous to AKAP was up regulated at E15 when cortical cells are undergoing active axogenesis. The expression pattern of this cDNA was confirmed by Real Time PCR. Our findings suggest a possible function for AKAP 450 in the regulation of the state of phosphorylation of centrosomal components during the initial stages of synapses formation during the establishment of Cortico-Thalamic connection. [source] Modeling and inferential control of the batch acetylation of celluloseAICHE JOURNAL, Issue 6 2006Anshul Dubey Abstract The batch acetylation of cellulose involves two main stages, acetylation followed by hydrolysis. Mathematical models were constructed for these processes using reaction parameters obtained from earlier publications. The two models were then combined, along with a model predicting the cellulose feedstock moisture content. The overall temperature profiles as well as the final degree of acetylation and polymerization were shown to match the data obtained from a commercial process. From the results of the model and the observations made in a typical process, it has been established that this process is highly sensitive to disturbances in the input streams that can result in unacceptable final properties of the batch. Because the exact disturbance occurring in a batch cannot be identified and measured, inferential control is used to formulate an intrabatch control strategy. Support vector regression is used to make predictions on the final properties of the batch. These predictions, along with the model of the hydrolysis stage, are used to estimate the inputs that, when applied during hydrolysis, can counter the disturbances caused during the acetylation stage. Simulations show that this hydrolysis control strategy can improve the average batch properties of cellulose acetate required for subsequent processing. © 2006 American Institute of Chemical Engineers AIChE J, 2006 [source] Conditions for Infection of Apple by Phytophthora syringaeJOURNAL OF PHYTOPATHOLOGY, Issue 4 2003D. C. Harris Abstract The processes leading to Phytophthora fruit rot were divided into two main stages for the purposes of investigating the effects of temperature and duration of wet periods on pathogen development: oospore germination and infection of fruit by zoospores. It was found that the first stage was markedly affected by temperature over the range 10,20°C and required a wet period of 4,7 days. At 18 and 20°C, activation was low regardless of the length of the wet period. Once oospore germination (first stage) had occurred, free water was necessary for only a few hours for fruit infection (second stage) to occur, but the incidence of infection rose rapidly over the first 48 h, regardless of temperature over the range 10,20°C. From the data obtained, mathematical models were produced relating the incidence of Phytophthora fruit rot to the two weather variables. These models can be used to develop a weather-based risk assessment system for the disease. [source] Microscopic studies of the influence of main exposure time on parameters of flexographic printing plate produced by digital thermal methodMICROSCOPY RESEARCH AND TECHNIQUE, Issue 10 2009Liliya Harri Abstract The digital thermal technology of producing flexographic printing plates from photopolymer plates is one of the newest technologies. This technology allows to develop flexographic plates without the use of any solvent. The process of producing flexographic printing plates by the digital thermal method consists of several main stages: back exposure, laser exposure, main exposure, thermal development, post exposure, and light finishing. The studies carried out with the use of optical stereoscopic microscopy allowed to determine the effect of time of main exposure to ultraviolet radiation on the dot area, diameter, and edge factor of halftone dots reproduced on flexographic printing plate produced by the digital thermal method, as well as on the quality of reproducing the surface and on the profiles of free-standing printing microelements. The results of the microscopic studies performed have allowed to define the criteria of establishing optimum time of main exposure of photopolymer plates used in the digital thermal technology of producing flexographic printing plates. A precise definition of the criteria for determining the optimum time of main exposure will enable to reduce the time-consuming control tests and to eliminate errors in both the process of manufacturing flexographic printing plates and in the printing process carried out with the use of such plates. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc. [source] Detection of Escherichia coli using immunomagnetic separation and bacteriophage amplification coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry,RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 3 2003Angelo J. Madonna The application of whole cell analysis by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has emerged as a valuable tool for rapidly identifying/detecting bacteria. This technique requires minimal sample preparation and is simple to perform, but is generally limited to purified samples of bacteria at concentrations greater than 1.0,×,106 cells/mL. In this paper, we describe a bacterial detection method that integrates immunomagnetic separation with bacteriophage amplification prior to MALDI-MS analysis. The developed method consists of three main stages: (1) isolation of a target bacterium by immunomagnetic separation; (2) infection of the immuno-captured bacterium with a lytic bacteriophage; and (3) assay of infected medium for bacteriophage progeny using MALDI-MS to produce a molecular weight signal for the virus capsid protein. With this technique, the presence of Escherichia coli in broth was determined in less then 2 h total analysis time at a concentration of ,5.0,×,104 cells/mL. Copyright © 2002 John Wiley & Sons, Ltd. [source] Orogenic Gold Mineralization in the Qolqoleh Deposit, Northwestern IranRESOURCE GEOLOGY, Issue 3 2007Farhang Aliyari Abstract The Qolqoleh gold deposit is located in the northwestern part of the Sanandai-Sirjan Zone, northwest of Iran. Gold mineralization in the Qolqoleh deposit is almost entirely confined to a series of steeply dipping ductile,brittle shear zones generated during Late Cretaceous,Tertiary continental collision between the Afro-Arabian and the Iranian microcontinent. The host rocks are Mesozoic volcano-sedimentary sequences consisting of felsic to mafic metavolcanics, which are metamorphosed to greenschist facies, sericite and chlorite schists. The gold orebodies were found within strong ductile deformation to late brittle deformation. Ore-controlling structure is NE,SW-trending oblique thrust with vergence toward south ductile,brittle shear zone. The highly strained host rocks show a combination of mylonitic and cataclastic microstructures, including crystal,plastic deformation and grain size reduction by recrystalization of quartz and mica. The gold orebodies are composed of Au-bearing highly deformed and altered mylonitic host rocks and cross-cutting Au- and sulfide-bearing quartz veins. Approximately half of the mineralization is in the form of dissemination in the mylonite and the remainder was clearly emplaced as a result of brittle deformation in quartz,sulfide microfractures, microveins and veins. Only low volumes of gold concentration was introduced during ductile deformation, whereas, during the evident brittle deformation phase, competence contrasts allowed fracturing to focus on the quartz,sericite domain boundaries of the mylonitic foliation, thus permitting the introduction of auriferous fluid to create disseminated and cross-cutting Au-quartz veins. According to mineral assemblages and alteration intensity, hydrothermal alteration could be divided into three zones: silicification and sulfidation zone (major ore body); sericite and carbonate alteration zone; and sericite,chlorite alteration zone that may be taken to imply wall-rock interaction with near neutral fluids (pH 5,6). Silicified and sulfide alteration zone is observed in the inner parts of alteration zones. High gold grades belong to silicified highly deformed mylonitic and ultramylonitic domains and silicified sulfide-bearing microveins. Based on paragenetic relationships, three main stages of mineralization are recognized in the Qolqoleh gold deposit. Stage I encompasses deposition of large volumes of milky quartz and pyrite. Stage II includes gray and buck quartz, pyrite and minor calcite, sphalerite, subordinate chalcopyrite and gold ores. Stage III consists of comb quartz and calcite, magnetite, sphalerite, chalcopyrite, arsenopyrite, pyrrhotite and gold ores. Studies on regional geology, ore geology and ore-forming stages have proved that the Qolqoleh deposit was formed in the compression,extension stage during the Late Cretaceous,Tertiary continental collision in a ductile,brittle shear zone, and is characterized by orogenic gold deposits. [source] Mineralogy, Geochemistry, and Age Constraints on the Beni Bou Ifrour Skarn Type Magnetite Deposit, Northeastern MoroccoRESOURCE GEOLOGY, Issue 1 2002Mohammed EL RHAZI Abstract: The Beni Bou Ifrour deposit of northeastern Morocco is a skarn type magnetite deposit. K-Ar age determination suggests that the mineralization occurred at 7.040.47 Ma. The spatial relationship between skarn and dikes of microgran-odiorite derived from the batholith of Wiksane Granodiorite, and the similarity of age (8.020.22 Ma), confirms that the Wiksane Granodiorite is the igneous rock most probably related to mineralization. The skarn is distributed asymmetrically in the limestone, and magnetite ore was developed just below the calc-silicate skarn as two parallel beds separated by 100 m of barren limestone and schist. The mineralization can be divided into three stages. The early stage is characterized by the formation of calc-silicate minerals, mainly clinopyroxene (80,70 % diopside) and garnet (early almost pure andradite to the late 60 % andradite). The main stage is characterized by the formation of a large amount of magnetite. Epidote and quartz formed simultaneously with magnetite. Fluid temperatures exceeded 500 C during the early to main stages. Fluid with very high salinity (50,75 wt% NaCl equiv.) was responsible for the formation of the magnetite ore. The oxygen isotope composition, together with the fluid inclusion data, suggests that magmatic fluid was significant for the formation of calc-silicate skarn minerals and magnetite. Low temperature (-230C) and low salinity (-10 % NaCl equiv.) hydrothermal fluids dominated by meteoric water were responsible for the late stage quartz and calcite formation. [source] On Freedom And Responsibility: Remarks On Sartre, Levinas And DerridaTHE HEYTHROP JOURNAL, Issue 1 2000Holger Zaborowski This article looks at some main stages of contemporary thought about freedom and responsibility and outlines an account of important stages of 20th century philosophy as well. Whereas the early Sartre particularly coined the notion of infinite freedom, his later writings, Levinas and Derrida (re-)discovered the conception of infinite responsibility. The article draws attention to the questions which arise out of these understandings of both responsibility and freedom and asks whether these issues can be answered from a purely secular point of view. The last part is devoted to the role of God in current philosophical considerations about responsibility and freedom. [source] Feedback for improving staff training and performance in behavioral treatment programs,BEHAVIORAL INTERVENTIONS, Issue 1 2008Lucius Arco This paper reviewed observational studies that examined feedback for changing staff performance in behavioral treatment programs for clients with cognitive, developmental, or psychiatric disorders. The research findings were integrated into the main stages of staff training and management: pretraining, training, and posttraining. Specific recommendations for using feedback are made including defining process and outcome form and content before training, providing on-the-job supervisory feedback while staff practice self-generated outcome feedback until competency is demonstrated, and after training, maintaining self-generated feedback with emphasis on evaluating staff and client interactions with social validity measures. Copyright © 2008 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||