Littérature scientifique sur le sujet « Middle Cla »
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Articles de revues sur le sujet "Middle Cla"
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BASU, S., U. RISÉRUS, A. TURPEINEN et B. VESSBY. « Conjugated linoleic acid induces lipid peroxidation in men with abdominal obesity ». Clinical Science 99, no 6 (7 novembre 2000) : 511–16. http://dx.doi.org/10.1042/cs0990511.
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Conjugated linoleic acid (CLA) has been shown in experimental studies to have chemoprotective properties, and may decrease the deposition of body fat. CLA is prone to oxidation, and it has been suggested that increased lipid oxidation may contribute to the anti-tumorigenic effects of this agent. The present study investigates the urinary levels of 8-iso-prostaglandin F2α (8-iso-PGF2α), a major isoprostane, and of 15-oxo-dihydro-PGF2α, a major metabolite of PGF2α, as indicators of non-enzymic and enzymic arachidonic acid oxidation respectively after dietary supplementation with CLA in middle-aged men (mean age 53 years) with abdominal obesity for 1 month in a randomized controlled trial. Significant increases in the levels of both 8-iso-PGF2α and 15-oxo-dihydro-PGF2α in urine (P < 0.0001 and P = 0.0013 respectively) were observed after 1 month of daily CLA intake (4.2 g/day) as compared with the control group. The lipid peroxidation parameters had returned to their basal levels at 2 weeks after the cessation of CLA intake, and remained at the same levels for a further 2 weeks until the end of the study. CLA had no effect on serum α-tocopherol and γ-tocopherol levels, or on the urinary levels of 2,3-dinor-thromboxane B2. Thus CLA may induce both non-enzymic and enzymic lipid peroxidation in vivo in middle-aged men with abdominal obesity, without any side effects. The consequences of the increased lipid peroxidation after CLA supplementation are unknown.
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Listos, Piotr, Magdalena Gryzinska, Marcin Martychiewicz, Stephen Pointing, Albrecht Barton et Malgorzata Dylewska. « Caseous Lymphadenitis in Sheep in the Falkland Islands ». Acta Veterinaria 66, no 3 (1 septembre 2016) : 406–12. http://dx.doi.org/10.1515/acve-2016-0034.
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AbstractCaseous lymphadenitis (CLA), also called pseudotuberculosis, is a chronic and highly infectious disease of sheep and goats, subject to obligatory registration in the European Union. The EU law also applies to special territories, which include the Falkland Islands. On the Falkland Islands 99% of sheep and goats are slaughtered in one slaughterhouse, overseen by veterinary authorities, and approved for export to EU countries (mainly the UK). The export season begins about the middle of January and usually lasts 3-4 months. In the years 2013-2015 were examined 162 317 sheep, including 39 971 lambs, 35 357 yearlings and 86 989 mature rams. During the study lung tissue clippings were collected. During the 2013 season lesions were observed in 8 025 of animals (13.9% CLA). In 2014 lesions were noted in 7716 with CLA accounting for 13.91% and in 2015 lesions were noted in 5743 with CLA accounting for 11.7%. Further analysis of cases of CLA on the Falkland Islands seems interesting, as they are British overseas territories and therefore part of the European Union.
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Briones, Claudia. « Research through Collaborative Relationships : A Middle Ground for Reciprocal Transformations and Translations ? » Collaborative Anthropologies 9, no 1-2 (2016) : 32–39. http://dx.doi.org/10.1353/cla.2016.0010.
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Holdaway, Marcelle. « Field work in potential gas fields, middle ground or war zone : enhancing accountability by shining a light on difference ». foresight 20, no 1 (12 mars 2018) : 84–104. http://dx.doi.org/10.1108/fs-07-2017-0036.
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Purpose As a key element of corporate accountability, social and environmental accounting (SEA) has failed to yield significant results in terms of firms embracing goals other than financial profitability. Influenced by the work of critical accountants on dialogic accounting, the study rejects binary frameworks and aims to contribute to an essential element of SEA, stakeholder engagement. Design/methodology/approach Business concerned with unconventional gas (UCG) extraction was chosen from numerous vehicles suited to examining multiple views on contested issues. The research explores perspectives expressed by community, while also including perspectives of one gas firm. Research is viewed through the lens of critical futures theory and methodology causal layered analysis (CLA) in the analysis of the interviews at the case study site in Australia. In addition, to broaden the understanding of “accountability”, participants captured their own views through images that they interpreted in the interviews. This methodology is known as photovoice. Findings Findings suggest that CLA enables access to multiple, complex and nuanced perspectives and various ways of knowing, some of which are less conscious. Research limitations/implications Accessing multiple perspectives, including marginalized voices, gives rise to the potential to then collaboratively develop a more inclusive set of solutions to critically examine, and the CLA methodology appears to provide a fuller story, address “blindness” and enable a clearer “seeing”. This suggests access to new understandings. These two potentials should be further explored through follow up research. Practical implications This practice-based methodology involving civil society could provide SEA accounting practitioners with a greater range of possibilities; they would therefore benefit from incorporating “CLA thinking” as a basis in developing a pluralist, democratic and transformative approach to stakeholder engagement. Social implications The study is an initial contribution in an ambitious task of democratizing accounting and accountability. Originality/value The study addresses a gap in accounting and accountability research by applying a critical futures theory and a practice-based method.
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Minkkinen, Matti, Sirkka Heinonen et Marjukka Parkkinen. « Drilling and Blasting to Learn Scenario Construction : Experimenting with Causal Layered Analysis as a Disruption of Scenario Work ». World Futures Review 11, no 2 (21 mai 2018) : 110–21. http://dx.doi.org/10.1177/1946756718774940.
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Scenario thinking is one of the key elements of futures studies, and therefore, “Scenario Thinking” is one of the first compulsory courses in the Master’s Degree Programme in Futures Studies at the University of Turku. Scenario methods are continuously evolving, and our educational practices must reflect recent developments while giving a clear outline of the big picture. Furthermore, increasing interest is being taken in hybrid methods, and such hybridity can also be introduced to teaching scenario thinking. This article discusses an experiment of using causal layered analysis (CLA) to complement and deepen scenarios made by student groups for a Finnish company during an introductory course on scenario thinking. During a first-year master’s degree course, a two-hour CLA session was conducted, and student groups were instructed to include the results into their scenario reports. From a methodological point of view, we discuss using CLA as a disruption in the middle of the scenario process to increase reflexivity. From a pedagogical point of view, we discuss how a relatively complex method combination (CLA and scenarios) can be made accessible to first-year master’s students conducting their first scenario study. As material, we use our own firsthand experiences from the scenario course and the CLA session as well as a subsequent survey with students. The intention of the paper is to quickly distribute educational practices for assessment by the futures education community and, thus, contribute to improving the state of futures studies and foresight education.
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Mack, Ines, Mike Sharland, Janneke M. Brussee, Sophia Rehm, Katharina Rentsch et Julia Bielicki. « Insufficient Stability of Clavulanic Acid in Widely Used Child-Appropriate Formulations ». Antibiotics 10, no 2 (23 février 2021) : 225. http://dx.doi.org/10.3390/antibiotics10020225.
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Amoxicillin-clavulanic acid (AMC) belongs to the WHO Essential Medicines List for children, but for optimal antimicrobial effectiveness, reconstituted dry powder suspensions need to be stored in a refrigerated environment. Many patients in low- and middle-income countries who are sold AMC suspensions would be expected not to keep to the specified storage conditions. We aimed to assess the stability of both ingredients in liquid formulations and dispersible tablets, combined with nationally representative data on access to appropriate storage. Degradation of amoxicillin (AMX) and clavulanic-acid (CLA) was measured in suspensions and dispersible tablets commercially available in Switzerland at different ambient temperatures (8 °C vs. 28 °C over 7 days, and 23 °C vs. 28 °C over 24 h, respectively). Data on access to refrigeration and electricity were assessed from the USAID-funded Demographic and Health Survey program. In suspensions, CLA degraded to a maximum of 12.9% (95% CI −55.7%, +29.9%) at 8°C and 72.3% (95% CI −82.8%, −61.8%) at a 28 °C ambient temperature during an observation period of 7 days. Dispersible tablets were observed during 24 h and CLA degraded to 15.4% (95% CI −51.9%, +21.2%) at 23 °C and 21.7% (−28.2%, −15.1%) at a 28 °C ambient temperature. There is relevant degradation of CLA in suspensions during a 7-day course. To overcome the stability challenges for all active components, durable child-appropriate formulations are needed. Until then, prescribers of AMC suspensions or pharmacists who sell the drug need to create awareness for the importance of proper storage conditions regarding effectiveness of both antibiotics and this recommendation should be reflected in the WHO Essential Medicines List for children.
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Oh, Seung-Lyul, Sang-Rok Lee, Andy V. Khamoui, Edward Jo, Bong-Sup Park, Michael J. Ormsbee, Lynn B. Panton et al. « Effects Of CLA/n-3 and Resistance Training on Muscle Quality in Middle-aged Mice During High-fat Diet ». Medicine & ; Science in Sports & ; Exercise 46 (mai 2014) : 588. http://dx.doi.org/10.1249/01.mss.0000495233.08381.58.
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Rubin, Diana, Julia Herrmann, Daniela Much, Maria Pfeuffer, C. Laue, P. Winkler, Ulf Helwig et al. « Influence of different CLA isomers on insulin resistance and adipocytokines in pre-diabetic, middle-aged men with PPARγ2 Pro12Ala polymorphism ». Genes & ; Nutrition 7, no 4 (8 mars 2012) : 499–509. http://dx.doi.org/10.1007/s12263-012-0289-3.
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Claes, Jeroen. « Cognitive and geographic constraints on morphosyntactic variation ». Current trends in analyzing syntactic variation 31 (31 décembre 2017) : 30–55. http://dx.doi.org/10.1075/bjl.00002.cla.
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Abstract In this paper, I examine whether the variation patterns of haber pluralization (e.g., hubo/hubieron fiestas ‘there was/were parties’) in Peninsular Spanish corroborate the hypothesis elaborated in earlier work that the phenomenon constitutes a competition between two variants of the presentational construction with haber that is constrained by domain-general cognitive constraints on spreading activation. In addition, this paper examines whether haber pluralization is incrementing in frequency in particular Peninsular regions and whether or not the phenomenon is spreading geographically. To meet these objectives, I analyze a dataset of more than 7,500 cases of haber + plural NP, which were culled from two publicly available data sources: the Corpus Oral y Sonoro del Español Rural (which represents only rural speakers born before the 1940s; Fernández-Ordóñez 2005-) and Twitter (which represents mainly young and middle-aged speakers). The results of a mixed-effects logistic regression analysis that tests the effects of tense, the absence/presence of negation, typical action-chain position of the noun, the regional origin of the examples, and the data sources support the competition hypothesis. This model also supports that pluralized haber is spreading westward from its epicenters (Valencia, Barcelona, and Murcia), while also incrementing in frequency in northern, eastern and southern Spain. However, its frequency appears to be declining in central Spain. A geographically more detailed, but similar picture is obtained with three generalized additive mixed models that test the effects of geography on the total dataset as well as on each of the two subcorpora.
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Miremadi, Tahereh. « Transitional foresight : MLP as the theoretical underpinning of CLA : the case of the water sector of Iran ». foresight 23, no 4 (26 février 2021) : 385–402. http://dx.doi.org/10.1108/fs-04-2020-0043.
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Purpose The paper aims to complement the six pillars analysis with the multi-level perspective to make it more systematic and policy relevant. Design/methodology/approach Take the innovation system foresight as the exemplar; the paper asks if the other systemic approaches to innovation can function as the middle range theory and underpin critical future studies. To answer, the paper combines the six-pillar approach (SPA) with the multilevel perspective (MLP) and builds “transitional foresight”. Then it takes the fourth pillar; transitional causal layered analysis and applies it to a case study: water stress in Iran. The paper concludes noting that in transitional foresight, the borderlines, the players and the orientations of the foresight are clearer than the six-pillar analysis. Findings The SPA and MLP-integrated framework make a powerful research instrument for transitional foresight. Research limitations/implications The paper applied the integrated framework to a case “water system in Iran”. But the framework should be applied in different cases in different countries to test its applicability. Practical implications The suggested framework can be used as a heuristics for the students and researchers who want to engage with the emancipatory perspective of the six-pillar approach and need to have an academic methodology with rigor and granularity. Originality/value The six-pillar approach of Sohail Inayatullah and the multilevel perspective of Geels can combine to make a powerful heuristic for transitional foresight.
Thèses sur le sujet "Middle Cla"
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GHAFFARI, RASSA. « Gender through Generations : ruoli e rappresentazioni di genere tra due generazioni della classe media di Tehran ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2020. http://hdl.handle.net/10281/277249.
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L’obiettivo della presente ricerca è di investigare le trasformazioni delle rappresentazioni e narrazioni dei ruoli di genere di due campioni di uomini e donne iraniani/e della classe media di Tehran, appartenenti a due generazioni differenti: il primo gruppo è composto da individui nati tra il 1960 e il 1969, ed appartenenti perciò a quella che la letteratura scientifica internazionale definisce Generazione X. Il secondo gruppo include giovani donne e uomini nate/i tra il 1990 e il 1999, definiti come membri della Generazione Millennial.
Avvalendosi di una metodologia di ricerca mista, composta da analisi documentaria, un’analisi secondaria di dati statistici e interviste narrative con uomini e donne di entrambe le generazioni, questo studio ha permesso di analizzare le complessità e contraddizioni insite nei processi di elaborazione e negoziazione delle identità di genere di questi/e attori e attrici sociali. A
d una interpretazione spesso semplicistica e sterotipizzata del mutamento sociale come ineluttabile e lineare processo da modelli e comportamenti “tradizionali” ad uno non meglio identificata nozione di “modernità”, la ricerca contrappone una lettura basata sul concetto di “bricolage culturale post-moderno”: un creativo processo di costruzione di significati attraverso la rielaborazione di elementi ed istanze precedenti e nuove, in cui il soggetto può operare scelte innovative e consapevoli in accordo con le proprie condizioni ed attitudini.The aim of the present research is to investigate the transformations of the representations and narrations of gender roles among two samples of Iranian men and women of Tehran’s middle class, belonging to two different generations: the first group is composed of individuals born between 1960 and 1969, and therefore belonging to what the international scientific literature defines Generation X. The second group includes young women and men born between 1990 and 1999, defined as members of the Millennial Generation. Using a mixed research methodology, consisting of documentary analysis, a secondary analysis of statistical data and narrative interviews with men and women of both generations, this study allowed us to deepen the complexities and contradictions intrinsic of the processes of elaboration and negotiation of gender identity among these social actors. Instead of an often simplistic and sterotyped interpretation of social change as an ineluctable and linear process from "traditional" models and behaviors to an unidentified notion of "modernity", the research contrasts the concept of "post-modern cultural bricolage": a creative process of construction of meanings through the rielaboration of previous and new elements and instances, in which the subject can make innovative and conscious choices in accordance with his/her own conditions and attitudes.
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Bornfield, Alva Jo Anne Gail. « A CBA model's effect on middle school students in math achievement ». Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185934.
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The present study was an investigation of the effects of a CBA model on mathematical achievement of middle school students. Nine subjects in the seventh and eighth grades were selected to participate in the study. A multiple baseline single subject design was used. Results indicated that a CBA model designed in the form of a pullout program can be very effective in identifying and remediating problems in mathematics for middle school students who are at-risk for failing mathematics. Implications of the current findings for the use of a CBA model were discussed. The use of a CBA model for students identified as at-risk for failing mathematics in middle school was supported.
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Armitage, Thomas M. « A bioeconomic model of the middle Atlantic surf clam (Spisula solidissima) fishery ». W&M ScholarWorks, 1985. https://scholarworks.wm.edu/etd/1539616551.
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A bioeconomic simulation model of the middle Atlantic surf clam (Spisula solidissima) fishery has been developed from a survey of biological and econometric relationships. While identifying the biological input parameters available in the literature, the economic submodel of the fishery has been developed with price and landings time series data, and with data obtained through the use of survey questionnaires and interviews with surf clam fishermen and processors. Alternative management scenarios in the fishery have been evaluated from industry costs in both the harvesting and processing sectors and analysis of the demand for raw product confronting surf clam fishermen. Multiple regression analysis of time series data indicates that surf clam ex-vessel prices may be negatively related to surf clam landings whereas hard clam prices are positively related to ex-vessel ocean quahog prices and ex-vessel oyster prices. The strength of this relationship confirms the status of ocean quahogs as very close substitutes for surf clams. The results of case studies using the model suggest that the Mid-Atlantic Fishery Management Council has followed a prudent course of action in managing the surf clam fishery. The model also projects that, (1) larger yield quotas may be possible in the immediate future without jeopardizing surf clam population stability, (2) overcapitalization in the fishery appears to remain a problem, and (3) the economic outlook for the operators of small vessels remains relatively bleak.
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Picariello, Adriana. « The Effects of Climate Change on the Population Ecology of the Atlantic Surf Clam, Spisula solidissima, in the Middle Atlantic Bight ». W&M ScholarWorks, 2006. https://scholarworks.wm.edu/etd/1539617848.
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Shen, Jingyi. « Chemical and isotopic analysis in the investigation of glazes from northern China and the Middle East, 7th-14th centuries AD ». Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/48201/.
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Both Chinese and Islamic glazed ceramics played a significant role in the history of ancient ceramic production. Moreover, it was innovation in glazes that made the Chinese and Islamic ceramics constantly innovative in various categories with different manufacturing techniques. This study applies chemical and isotopic analyses to investigate the manufacturing techniques and provenances of different types of glazes from Northern China and the Middle East, and extends the use of Sr isotopic analysis to investigate raw materials and glaze recipes used to making lime/alkaline glazes in Northern China and the Middle East for the first time. By chemical compositions of the lead glazes, the glazing techniques used to produce Chinese Tang Sancai lead glazes and splashed lead glazes from the Middle East have been identified. The mixture of lead oxide plus quartz/quartz sand was used for making both Chinese Tang Sancai glazes and Islamic splashed lead glazes. Besides, for the Chinese lead glazes, the trace element and lead isotopic analyses of them have been effective in grouping glazes made in different production kiln sites, and hence associating the Tang Sancai wares excavated from archaeological sites of unknown origin with their production centres. Furthermore, by comparing the lead isotopic ratios of Islamic lead glazes and those of lead ore deposits, the possible sources of lead used for making lead glazes can be determined, although more than one source was suggested due to the overlap of Pb isotopic ratios of different lead ore sources in some cases. This study is the first time that Sr isotopic analysis has been applied to the lime/alkaline glazes from Northern China and the Middle East. It has revealed that Sr isotopic compositions of lime/alkaline glazes from Northern China and the Middle East have been very effective in providing information on the glaze recipes and characteristics of raw materials used for making them. Based on Sr isotopic compositions, the case study of Nothern Chinese lime glaze has identified that the Yaozhou celadon glaze was probably produced by local ‘Fuping glaze stone’ combined with botanic ash. Besides, the case study of the Middle East alkaline glaze has suggested that the Raqqa ware glaze was probably made by ‘Cenozoic sand’ containing a certain content of limestone grains and feldspar and that botanic ash was used as a flux.
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Carlson, Justin Nels. « MIDDLE TO LATE HOLOCENE (7200-2900 CAL. BP) ARCHAEOLOGICAL SITE FORMATION PROCESSES AT CRUMPS SINK AND THE ORIGINS OF ANTHROPOGENIC ENVIRONMENTS IN CENTRAL KENTUCKY, USA ». UKnowledge, 2019. https://uknowledge.uky.edu/anthro_etds/40.
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Though some researchers have argued that the Big Barrens grasslands of Kentucky were the product of anthropogenic land clearing practices by Native Americans, heretofore, this hypothesis had not been tested archaeologically. More work was needed to refine chronologies of fire activity in the region, determine the extent to which humans played a role in the process, and integrate these findings with the paleoenvironmental and archaeological record. With these goals in mind, I conducted archaeological and geoarchaeological investigations at Crumps Sink in the Sinkhole Plain of Kentucky. The archaeological record and site formation history of Crumps Sink were compared with environmental and archaeological data from the Interior Low Plateaus and Southern Appalachian Mountains for an understanding of how the site fits into the larger story of human-environmental interactions in the Eastern Woodlands. Based on the data recovered, I argue that through land burning Archaic hunter-gatherers were active managers of ecosystems to a greater degree than previously acknowledged.
Excavations at Crumps Sink revealed stratified archaeological deposits spanning the late Middle Archaic to Terminal Late Archaic periods. Radiocarbon dates and an analysis of projectile point typologies provided information on the chronological and cultural history of the site. Magnetic susceptibility, loss-on-ignition, plant available phosphorous, and soil micromorphological analyses were conducted to examine landform dynamics in response to environmental change and to trace the anthropogenic signature created by human activities at the site. Masses of lithic debitage, animal bone, and burned sediment nodules per ten-cm-level provide an indication of human occupation intensity and shifting activities over time. Radiocarbon dates were used to reconstruct rates of sediment accumulation in the sink. These varying datasets were considered together for a holistic understanding of localized environmental and anthropogenic impacts on the landform.
Between 7200 and 5600 cal. BP, during the Middle Holocene Thermal Maximum and corresponding with the late Middle Archaic period, sediment accumulation was sustained with one identifiable episode of very weak soil development. Background magnetic and chemical signatures in the soils were greater than they were at pre-occupation levels, demonstrating that human activities left a lasting imprint in soils as early as the late Middle Archaic period. Between 5600 and 3900 cal. BP, periods of diminished sedimentation led to more pronounced episodes of soil formation. However, these soil horizons are interposed by pulses of enhanced sediment accumulation. These soil data may signal shifting environmental regimes during the Middle to Late Holocene transition. Between 5600 and 3900 cal. BP scattered plant ash, elevated masses of burned sediment nodules, and pestle fragments in Late Archaic deposits suggest that hunter-gatherers were intensively processing nut mast, potentially in association with early forest clearance and silviculture. Botanical assemblages from a coincident archaeological sequence at the Carlston Annis site in the nearby middle Green River region has demonstrated woodland disturbance and potential silviculture in central Kentucky during this time.
During the Late Archaic and Terminal Late Archaic periods (3900-3000 cal. BP), substantial plant ash deposition occurred in a stratum that accumulated relatively quickly. Very low burned sediment nodule masses in this deposit indicate that combustion features were not common in the immediate vicinity and that elevated frequencies of plant ash were the result of burning on a broader expanse of the surrounding landform. Chronologically, the zone with enhanced plant ash deposition is coeval with previously demonstrated occurrences of increased forest fires, grassland expansion, and a shift to early horticultural economies throughout the region. Soil development occurred after 3000 cal. BP, and this episode of landform stability may have lasted for over two millennia until being capped by sediment accumulation from historic agriculture.
The late Middle Archaic through Terminal Late Archaic data from Crumps Sink demonstrate that hunter-gatherer activities left lasting signatures in soils in Kentucky. The data from the Late Archaic to Terminal Late Archaic periods (ca. 5600-3000 cal. BP) may indicate intentional land burning by hunter-gatherers to create anthropogenic environments, first for silviculture and then for early plant domestication. This forces a rethinking of labor and subsistence systems within hunter-gatherer societies. Thus, if hunter-gatherers were utilizing long-term forest management methods, they were employing a delayed-return economic system relying on labor investment and negotiated understandings about land tenure. Further characterization of the origin of fire management activities will help us to elucidate the nature of incipient indigenous plant domestication in the Eastern Woodlands.
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Rêgo, Eric Siciliano. « Variation of minerals and clay minerals recorded in the Neo-Tethys (central Turkey) : new evidence of climatic changes during the middle Eocene ». Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/21/21136/tde-23032018-152550/.
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Minerals and clay minerals in continental sedimentary successions are valuable tools for reconstructing past environmental conditions. Given the state of preservation of clays minerals, it is possible to identify how they were formed, providing clues about continental weathering conditions (inherited minerals) and geochemical conditions in the water column (neoformed or transformed). This study presents new mineralogical data from the Baskil section, a highly preserved middle Eocene succession in the Neo-Tethys (central Turkey). A gradual shift from a well-crystalline illite and chlorite interval (subsection I) to a detrital smectite dominant interval (subsection II) characterizes a change in source area from metamorphic to igneous rocks and changes from physical to chemical weathering conditions on land. This period coincides with the Middle Eocene Climatic Optimum (MECO), indicating a mineralogical signature of the event. Higher content of terrigenous input being deposited from 40.5 to 40 Ma caused a dilution effect of the carbonate materials as calcite and dolomite significantly decreases. Authigenic palygorskite showed an increasing trend from the middle to the uppermost portion of the section, indicating favorable conditions in the water column for its formation. We assume that conditions in the ocean circulation changed after 40 Ma, forming a stratified water column with warmer and saline conditions at greater depths, favoring palygorskite and possibly authigenic dolomite precipitation. The mineralogical evolution of the Baskil section reflects how sources and weathering regimes changed through time, and how these changes can be related to global (i.e. MECO) and/or local to regional processes.Minerais e argilominerais em sucessões sedimentares são excelente ferramentas para a reconstrução de condições ambientais. Dado o estado de preservação dos argilominerais, é possível identificar como eles foram formados, fornecendo informação sobre as condições de intemperismo no continente e sobre condições geoquímicas na coluna d\'água. Este estudo apresenta novos dados mineralógicos da seção de Baskil, uma sucessão do Eoceno médio altamente preservada no Neo-Tethys (Turquia central). Uma mudança na assembléia mineralógica com maiores concentrações de ilita e clorita (subseção I) para um intervalo dominante de esmectita detrítica (subseção II) caracteriza uma mudança na área de fonte de rochas metamórficas para rochas ígneas e mudanças de condições de intemperismo físico para intemperismo químico. Este período coincide com o Ótimo Climático do Eoceno Médio (MECO), indicando uma assinatura mineralógica do evento. A paligorsquita autigênica teve um aumento na porção media e superior da seção, indicando condições favoráveis na coluna de água para a sua formação. Possívelmente as condições na circulação do oceano naquela região mudaram após 40 Ma, formando uma coluna de água estratificada com condições mais quentes e salinas em profundidades maiores, favorecendo precipitação de paligorsquita e dolomita. A evolução mineralógica da seção de Baskil reflete como as fontes e os regimes de intemperismo mudaram ao longo do tempo, e como essas mudanças podem estar relacionadas aos processos globais (e.g. MECO) e /ou a processos locais e regionais.
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Duboscq, Stéphanie. « Caractérisation des relations sociales des communautés du nord-est de la péninsule Ibérique entre la seconde moitié du Ve et la seconde moitié du IVe millénaire cal BC d'après l'étude des pratiques funéraires ». Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/405646.
Texte intégralRésumé :
Este trabajo de investigación tiene como objetivo obtener un mayor conocimiento de las mujeres de la prehistoria, con especial atención a sus condiciones de vida durante el neolítico medio en el noreste de la Península Ibérica, así como las relaciones que tenían con otros individuos (principalmente hombres) y el rol que tenían en su comunidad, a través del estudio de datos arqueológicos disponibles. El objetivo es también contribuir a una mayor comprensión de las comunidades del noreste de la Península Ibérica en su conjunto, en un momento, el neolítico medio, durante el cual los materiales circulaban, a veces, largas distancias, lo que refleja la existencia de complejas redes de intercambio. Estas redes parecen estar relacionadas, en Europa occidental, con la generalización de disimetrías sociales acompañadas por el enriquecimiento y la toma de poder por ciertos individuos o grupos de individuos. La existencia de estas disimetrías ya se ha considerado para el noreste de la Península Ibérica pero, ¿era el sexo una variable que influía en la naturaleza de las desigualdades jerárquicas?
Para lograr estos objetivos, me he interesado particularmente en el registro funerario, ya que los contextos de hábitat son poco conocidos debido a su mal estado de conservación. Se ha realizado un registro compuesto de 278 estructuras distribuidas entre 45 yacimientos, para un total de 370 individuos. Una tipología se ha llevado a cabo tomando como principal variable la autenticidad del carácter funerario de estas estructuras, con el fin de poner de relieve diferentes prácticas que podrían haber coincidido con diferentes realidades sociales y cronológicas. Con el fin de aclarar las cuestiones específicas de esta investigación, se realizaron análisis transversales a partir de la información procedente de los tres principales aspectos considerados en este estudio: la estructura, el ajuar funerario y el propio individuo.
Los resultados obtenidos han permitido distinguir una variedad de situaciones relacionadas con la cronología, el contexto global, el grado de participación de los diversos grupos humanos en las redes de intercambio y, probablemente, a particularidades regionales. Las desigualdades han sido destacadas en varios niveles: entre las regiones, entre yacimientos y entre individuos de un mismo yacimiento. La organización de estas sociedades habría sido, entonces, jerárquica. Algunos individuos, en su mayoría hombres, se distinguieron no solamente en relación con las mujeres sino también con otros hombres. Parece ser, también, que tenían una estrecha relación con las redes de intercambio sobre las cuales habrían ejercido un tipo de control. Sin embargo, a pesar de la identificación de diferencias entre hombres y mujeres, el sexo no tenía que ser el principal factor de disimetría entre los individuos en este contexto. Así mismo, los datos disponibles no sugieren que un grupo humano hubiese sido explotado debido al sexo de sus miembros.Ce travail de recherche a pour objectif de participer à l’obtention d’une meilleure connaissance des femmes de la Préhistoire, en s’intéressant tout particulièrement à leurs conditions de vie durant le Néolithique moyen au nord-est de la péninsule Ibérique, aux relations qu’elles entretenaient avec les autres individus (principalement les hommes) et à la place qu’elles occupaient dans leur communauté, et ce par le biais de l’étude des données archéologiques disponibles. Le but est également de contribuer à une plus grande compréhension des communautés du nord-est de la péninsule Ibérique dans leur ensemble à un moment, le Néolithique moyen, où des matériaux circulent parfois sur de longues distances, reflétant l’existence de réseaux d’échanges complexes. Ces réseaux semblent liés, en Europe de l’ouest, à la généralisation de dissymétries sociales, elles-mêmes accompagnées de l’enrichissement et de la prise de pouvoir par certains individus ou groupes humains. L’existence de ces dissymétries a déjà été envisagée pour le nord-est de la péninsule Ibérique, mais le sexe des individus était-il une variable influençant la nature d’inégalités hiérarchiques ? Afin d’atteindre ces objectifs, je me suis intéressée spécifiquement au domaine funéraire, les contextes d’habitat étant peu connus du fait de leur mauvaise conservation. Un corpus a été élaboré, composé de 278 structures réparties entre 45 sites, pour un total de 370 individus. Une typologie a été effectuée en prenant comme variable principale l’authenticité du caractère funéraire de ces structures, de manière à mettre en évidence différentes pratiques, qui pourraient correspondre à différentes réalités sociales ou chronologiques. En vue d’éclairer la problématique propre à cette recherche, des analyses transversales ont été menées à partir de l’information provenant des trois aspects principaux pris en considération dans cette étude : la structure, le mobilier funéraire et l’individu en lui-même. Les résultats obtenus ont permis de distinguer une diversité de situations, liées à la chronologie, au contexte global, au degré de participation des divers groupes humains aux réseaux d’échanges, et sans doute à des particularités régionales. Des inégalités ont été mises en évidence sur différentes échelles : entre régions, entre sites, entre individus d’un même site. L’organisation de ces sociétés serait donc bien hiérarchisée, et certains individus, principalement de sexe masculin, se distinguent non seulement par rapport aux femmes, mais aussi par rapport aux autres hommes. Ils sembleraient avoir un lien étroit avec les réseaux d’échanges, sur lesquels ils devaient exercer une forme de contrôle. Cependant, malgré la mise en évidence de différences entre hommes et femmes, le sexe ne devait pas être le principal facteur de dissymétries entre individus dans ce contexte, et les données disponibles ne permettent pas de dire qu’un groupe humain était exploité à cause du sexe des sujets le composant.
The purpose of this research is to contribute to the acquisition of a better knowledge of Prehistoric women, paying particular attention to their living conditions during the Middle Neolithic in the northeast of the Iberian peninsula, to the relations they had with the other individuals (especially men), and the place they occupied in their community, through the study of the available archaeological data. The goal is also to contribute to a greater understanding of the communities of the northeast of the Iberian Peninsula as a whole at a time, the Middle Neolithic, when raw materials and artifacts sometimes traveled long-distances, reflecting the existence of complex exchange networks. In Western Europe, these networks seem to be linked to the spread of social dissymmetry, which is itself accompanied by an enrichment and a power takeover by certain individuals or groups of people. The existence of this dissymmetry has already been envisaged for the northeast of the Iberian Peninsula, but was the sex of the individuals a variable influencing the nature of hierarchical inequalities? In order to explore these issues, I focus my research on funerary contexts. Indeed, settlement contexts are not well-known because of their poor conservation. A corpus of mortuary structures was elaborated, consisting of 45 sites, 278 structures and 370 individuals. A typology was constructed, taking as the main variable how reliable is a structure as a funerary context, so as to highlight different practices that could correspond to different social or chronological realities. In order to shed light on the issues specific to this research, transversal analyzes were carried out. Theses analyzes were based on the information coming from the three main aspects taken into account in this study: the burial structure, the grave goods and the dead individual. The results obtained made it possible to distinguish a variety of patterns, linked to the chronology, to the overall context, to the degree of participation of the various human groups in the exchange networks, and probably to regional particularities. Inequalities have been revealed on different scales: among regions, among sites and among individuals of the same site. The organization of these societies seems to have been hierarchized, and some individuals, mainly males, are distinguished not only in relation to women but also in relation to other men. They seem to have a close connection with the exchange networks, on which they could exercise some form of control. However, despite the evidence of gender differences, sex was probably not the main factor of dissymmetry among individuals in this context, and the available data does not allow for the conclusion that one human group was being exploited by another because of the sex of these individuals.
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Shuja, Jesper. « Öst och Väst : Kommer vi någonsin mötas ? Analys av hur Hollywood representerar människor från Mellanöstern. East and the West : Will we ever meet ? An analysis of how Hollywood represents people of the Middle East ». Thesis, Malmö högskola, Lärarutbildningen (LUT), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-33985.
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Då antagonismen mellan öst och väst forstätter att eskalera i vårt postindustriella samhälle är det viktigt att ta reda på de bidragande faktorer som leder till en fortsatt motsättning. Det är min uppfattning att Hollywood är en bidragande faktor till denna antagonism. Det är även min åsikt att Hollywood blir påverkade av USA:s Mellanösternpolitik i utformandet av de filmer där människor från Mellanöstern och islam porträtteras.Syftet med studien är att utifrån teorier såsom orientalism, stereotypering, representation och common-sense antaganden analysera nio utvalda Hollywoodfilmer. Tre från 1960-talet, tre från 1990-talet och tre från 2000-talet för att klarlägga hur människor från Mellanöstern framställs och hur islam representeras.Syftet är även att med hjälp av Faircloughs kritiska diskursanalys belysa hur samhället påverkar Hollywoods produktioner och hur dessa i sin tur påverkar samhället. Mot bakgrund av detta är Faircloughs trestegsmodell lämplig för att tydligöra det dialektiska samspel som existerar mellan samhälle och produktionen av film.Utifrån de teorier och metod som har presenterats har jag funnit att de nio utvalda filmerna framställer människor från Mellanöstern och islam på ett negativt sätt. Det har även varit möjligt att med hjälp av Faircloughs trestegsmodell tydligöra ett dialektiskt samspel mellan USA:s Mellanösternpolitik och Hollywood.In a time when antagonistic feelings continue to escalate in our postindustrial society, it tends to be vital to look for the contributing factors to why opposition seems to continue. It is my understanding that Hollywood is one of several factors to the ongoing animosity. It is also my belief that the ongoing US Middle Eastern policy has an influence on Hollywood, which has a direct impact on the production of movies that represent people of the Middle East and Islam.The purpose if this paper is to analyze nine selected Hollywood movies using theories such as Orentalism, stereotypes, representation and common-sense assumptions. The films will be taken from three separate decades, from the 1960s, 1990s and the 2000s. The function of the investigation is to determine how people of the Middle East and Islam are being represented.Another purpose is also to establish an understanding on how society affects Hollywood productions but also how these productions in turn affect society; this will be done by using Fairclough’s critical discourse analysis. Fairclough’s framework for CDA is ideal in determenating the ongoing dialectical relationship between society and the production of movies.By using the theories and method formerly presented, I have concluded that when analyzing the nine selected movies, people of the Middle East and Islam are being represented in a negative manner. It has also been possible to establish that there exists a dialectical relationship between US Middle Eastern policy and Hollywood by using Fairclough’s framework for CDA.
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Sanguras, Laila Y. « Construct Validation and Measurement Invariance of the Athletic Coping Skills Inventory for Educational Settings ». Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc984216/.
Texte intégralRésumé :
The present study examined the factor structure and measurement invariance of the revised version of the Athletic Coping Skills Inventory (ACSI-28), following adjustment of the wording of items such that they were appropriate to assess Coping Skills in an educational setting. A sample of middle school students (n = 1,037) completed the revised inventory. An initial confirmatory factor analysis led to the hypothesis of a better fitting model with two items removed. Reliability of the subscales and the instrument as a whole was acceptable. Items were examined for sex invariance with differential item functioning (DIF) using item response theory, and five items were flagged for significant sex non-invariance. Following removal of these items, comparison of the mean differences between male and female coping scores revealed that there was no significant difference between the two groups. Further examination of the generalizability of the coping construct and the potential transfer of psychosocial skills between athletic and academic settings are warranted.
Livres sur le sujet "Middle Cla"
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Biodiversity, California Institute for. Cal Alive ! : Classroom guide. Walnut Creek, CA : California Institute for Biodiversity, 2001.
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The C.A. Bayly omnibus. New Delhi : Oxford University Press, 2009.
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Bayly, C. A. The C.A. Bayly omnibus. New Delhi : Oxford University Press, 2009.
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1930-, Bolton W. F., dir. The Middle Ages. London : Penguin Books, 1993.
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Zhizheng, Wang, dir. Xianggang zhong chan jie ji chu jing guan cha. Xianggang : San lian shu dian, 2003.
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Duncan, Wu, dir. Old and Middle English poetry. Oxford, UK : Blackwell Pub., 2002.
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The Aqquyunlu : Clan, confederation, empire. Salt Lake City : University of Utah Press, 1999.
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Evolution and spatial organization of clan settlements : A case study of middle Ganga Valley. New Delhi : Concept Pub. Co., 1986.
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Yang, Yi, dir. Zhongguo zhong chan zhe diao cha : Lai zi Zhongguo she hui zhong chan jie ceng de quan wei bao gao. Beijing Shi : Tuan jie chu ban she, 2004.
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H, Newcomb Benjamin. Political partisanship in the American middle colonies, 1700-1776. Baton Rouge : Louisiana State University Press, 1995.
Trouver le texte intégralChapitres de livres sur le sujet "Middle Cla"
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Achard, Michel. « The impersonal value of demonstrative and middle constructions ». Dans Constructional Approaches to Language, 177–200. Amsterdam : John Benjamins Publishing Company, 2012. http://dx.doi.org/10.1075/cal.13.11ach.
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Wilford, Hugh. « America’s Great Game : The CIA and the Middle East, 1947–67 ». Dans Challenging US Foreign Policy, 99–112. London : Palgrave Macmillan UK, 2011. http://dx.doi.org/10.1057/9780230349209_6.
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Damnati, Brahim, et Hanane Reddad. « Abrupt Climatic Changes for the Last 13,000 Cal Years BP Using the Ifrah Lake Data (Middle Atlas, Morocco) ». Dans Advances in Intelligent Systems and Computing, 72–76. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-36671-1_7.
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Gelichi, Sauro. « Venice in the early middle ages. The material structures and society of ‘civitas aput rivoaltum’ between the 9th and 10th centuries ». Dans Urban identities in Northern Italy, 800-1100 ca., 251–71. Turnhout : Brepols Publishers, 2015. http://dx.doi.org/10.1484/m.scisam-eb.5.109864.
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Harris, Lucille E. « Sociopolitical Structural Tensions and the Dynamics of Culture Change in Middle-Range Societies of the Northern Plateau of Northwestern North America, ca. 1800–400 cal. B.P. » Dans The Evolution of Social Institutions, 387–417. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-51437-2_18.
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« RUGBY IN THE MIDDLE EAST ». Dans Khaki-clad Springboks, 5–27. African Sun Media, 2017. http://dx.doi.org/10.2307/j.ctv1nzg0hd.6.
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Salazar, Diego, Carola Flores, César Borie, Laura Olguín, Sandra Rebolledo, Manuel Escobar et Ariadna Cifuentes. « Economic Organization and Social Dynamics of Middle-Holocene Hunter-Gatherer-Fisher Communities on the Coast of the Atacama Desert (Taltal, Northern Chile) ». Dans Maritime Communities of the Ancient Andes, 74–100. University Press of Florida, 2020. http://dx.doi.org/10.5744/florida/9780813066141.003.0003.
Texte intégralRésumé :
Chapter 3 summarizes research on maritime adaptations at Middle Holocene (~7,500 to 4,500 cal BP) occupations of the southern extreme of the Atacama Desert, centered around Taltal on the north Chilean coast. Through this period, the authors see increasing population, complexity, and sedentism, but the social system comes to an abrupt end at 4,500 cal BP. In this hyperarid region, marine resources were always extremely important.
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Bissett, Thaddeus G., Stephen B. Carmody et D. Shane Miller. « Investigations at the Barnes Site (40DV307) ». Dans The Cumberland River Archaic of Middle Tennessee, 91–110. University Press of Florida, 2019. http://dx.doi.org/10.5744/florida/9781683400837.003.0006.
Texte intégralRésumé :
At the Barnes Site (40DV307) along the Cumberland River, two discrete shell-bearing deposits dating to the Late Archaic and Middle Woodland periods (approximately 3500 and 1800 cal BP respectively) are separated by a thick Early Woodland–period shell-free stratum dated between 2900 and 2000 cal BP. Alternating shell-bearing and shell-free deposits at sites elsewhere in the southern Ohio Valley have often been viewed as indicative of long-term changes in subsistence practices and traditions or large-scale environmental fluctuations affecting resource abundance. At Barnes, however, chronological, geoarchaeology, and paleoethnobotany data from shell-bearing strata recovered in 2010 and 2012 suggest that the two shell-bearing deposits mark the locations of shellfish processing at or near the river’s edge when the river channel was physically closer to the current site location. Particle-size data indicate that when the shell-free deposit accumulated, the site was situated in a low-energy depositional zone, suggesting that the river channel had shifted further to the west during that period of time.
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Miller, D. Shane, Thaddeus G. Bissett, Tanya M. Peres, David G. Anderson, Stephen B. Carmody et Aaron Deter-Wolf. « Geoarchaeology and Bayesian Statistical Modeling of Radiocarbon Dates from 40CH171, a Multicomponent Shell-Bearing Site in Cheatham County, Tennessee ». Dans The Cumberland River Archaic of Middle Tennessee, 75–90. University Press of Florida, 2019. http://dx.doi.org/10.5744/florida/9781683400837.003.0005.
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Using multiple lines of evidence from 40CH171, including opportunistic sampling, geoarchaeology analysis, and Bayesian radiocarbon modeling, this chapter constructs a site formation process narrative based on fieldwork conducted from 2009 to 2010 by the University of Tennessee, Middle Tennessee State University, and the Tennessee Division of Archaeology. This chapter argues that the shell-bearing strata were deposited relatively close to an active channel of the Cumberland River and/or Blue Creek during the Middle Holocene (ca. 7170–6500 cal BP). This was followed by an abrupt shift to sandier sediments, indicating that deposition after the termination of the shell-bearing deposits at the Middle Archaic/Late Archaic boundary took place in the context of decreasing distance from the site to the Cumberland River and Blue Creek.
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Rice, Prudence M. « The E Group as Timescape ». Dans Maya E Groups. University Press of Florida, 2017. http://dx.doi.org/10.5744/florida/9780813054353.003.0005.
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Small, hand-modeled, anthropomorphic figurines of fired clay are abundant in Middle Preclassic (1000–350 BCE) Mesoamerica, especially Central Mexico, the Isthmus, and regions to the south. They are variably present in the southern Maya lowlands and virtually absent in the northern lowlands, raising many questions about their meanings and uses. I propose that Middle Preclassic lowland Maya ceramic figurines: 1) were manipulated in integrative community renewal rituals associated with females and maize, and celebrated in early versions of E Groups; and, more speculatively, 2) were icons related to development of head-variant glyphs used in the script-iconography of the 260-day sacred almanac.
Actes de conférences sur le sujet "Middle Cla"
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Khan, Rizwan Ahmed, Mobeen Murtaza, Hafiz Mudaser Ahmad, Abdulazeez Abdulraheem, Muhammad Shahzad Kamal et Mohamed Mahmoud. « Development of Novel Shale Swelling Inhibitors Using Hydrophobic Ionic Liquids and Gemini Surfactants for Water-Based Drilling Fluids ». Dans SPE Middle East Oil & Gas Show and Conference. SPE, 2021. http://dx.doi.org/10.2118/204740-ms.
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Abstract In the last decade, hydrophilic Ionic liquids have been emerged as an additive in drilling fluids for clay swelling inhibition. However, the application of hydrophobic Ionic liquids as a clay swelling inhibitor have not been investigated. In this study, the combination of hydrophobic Ionic liquids and Gemini surfactant were studied to evaluate the inhibition performance. The novel combination of hydrophobic ionic liquid (Trihexyltetradecyl phosphonium bis(2,4,4-trimethyl pentyl) phosphinate) and cationic gemini surfactant (GB) was prepared by mixing various concentrations of both chemicals and then preparing water based drilling fluid using other drilling fluid additives such as rheological modifier, filtration control agent, and pH control agent. The wettability of sodium bentonite was determined by contact angle with different concentrations of combined solution. Some other experiments such as linear swelling, capillary suction test (CST) and bentonite swell index were performed to study the inhibition performance of ionic liquid. Different concentrations of novel combined ionic liquid and gemini surfactant were used to prepare the drilling fluids ranging from (0.1 to 0.5 wt.%), and their performances were compared with the base drilling fluid. The wettability results showed that novel drilling fluid having 0.1% Tpb-P - 0.5% GB wt.% concentration has a maximum contact angle indicating the highly hydrophobic surface. The linear swelling was evaluated over the time of 24 hours, and least swelling of bentonite was noticed with 0.1% Tpb-P - 0.5% GB wt.% combined solution compared to linear swelling in deionized water. Furthermore, the results of CST also suggested the improved performance of novel solution at 0.1% Tpb-P - 0.1% GB concentration. The novel combination The novel combination of hydrophobic ionic liquids and gemini surfactant has been used to formulate the drilling fluid for high temperature applications to modify the wettability and hydration properties of clay. The use of novel combined ionic liquid and gemini surfactant improves the borehole stability by adjusting the clay surface and resulted in upgraded wellbore stability.
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Shamsan, Abdulmalek, Alejandro De la Cruz et Walmy Jimenez. « Successful Barrier Enhancement Application of Epoxy Based Resin for Multiple Casing to Casing Annuli Having Tight Injectivity - Case Study from Saudi Arabian Peninsula ». Dans SPE Middle East Oil & Gas Show and Conference. SPE, 2021. http://dx.doi.org/10.2118/204780-ms.
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Abstract This study describes the approach used for enhancing the well integrity that was compromised with gas flow through a casing-casing annulus (CCA). Extremely tight injectivity at a CCA demands a solid free solution which not only can be injected but also resist high differential pressures to provide a long-term barrier in CCA. In this paper a successful leak remediation using an epoxy resin system helped the operator save a well and restart its production. Several pressure tests were conducted for identifying an extremely tight casing leak which was causing formation gas travelling to surface through the annulus. This issue required the customer to look for an efficient remedial solution to seal off the gas leakage and regain productivity. Due to the extremely low injectivity, a conventional cement squeeze or any solid laden particle-based squeeze approach was prone to fail. Alternatively, a tailored solid free epoxy resin system was placed in the annulus using an unconventional placement technique resulted in barrier enhancement and helped the operator place the well back into production. For a mature well flowing through 7 × 9 5/8‑in. and 9 5/8 × 13 3/8‑in., a tailored epoxy-based resin system formulation was placed in the well bore with modified surface operations procedures which helped in eliminating current annular pressure to regain well integrity and production. Remedial operations were performed from the surface by squeezing to seal off the gas coming from the annulus. A Tailored design derived from rigorous lab testing and perfect field execution resulted in CCA pressure remediation in a single attempt of the treatment injection, proving that the concept of using a solids-free resin to enhance existing deteriorated barriers is a reliable method. This epoxy resin system helped the operator to regain the well integrity and production in the shortest time without expensive well intervention operations. Epoxy resin based systems have been identified as a novel solution to remediate barrier integrity for well construction and workover operations, hence such case histories with enhanced operations procedures are helpful in increasing awareness of the benefits that can be attained in challenging high-pressure, low-injectivity environments, and can improve well economics.
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Connor, Brian J. « Ground-based Microwave Spectroscopy of the Middle Atmosphere ». Dans Optical Remote Sensing of the Atmosphere. Washington, D.C. : Optica Publishing Group, 1991. http://dx.doi.org/10.1364/orsa.1991.owb1.
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Ground-based microwave measurements of middle atmosphere constituents have made important contributions over the years. Among these are the most extensive series of mesospheric water vapor measurements to date1, the observation that antarctic ozone depletion does not extend to the upper stratosphere2, the only extant measurement of the diurnal variation of ClO3, the first observation of the diurnal variation of mesospheric ozone4, the first observation of very low concentrations of N2O in the polar vortex5, and the first detection of enhanced ClO in the antarctic lower stratosphere6.
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Guo, H. J., B. G. Xu, H. W. Yin, Z. T. Liu, M. J. Lv et J. L. Wang. « Development and First Application of Monobore Openhole Expandable Clad in the Tarim Oilfield ». Dans SPE/IADC Middle East Drilling Technology Conference and Exhibition. Society of Petroleum Engineers, 2018. http://dx.doi.org/10.2118/189410-ms.
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Alsubhi, A. M., A. M. Abduljabbar, K. Agazade et A. S. Alyami. « Well Integrity Improvement : CCA Preventive Actions in HPHT Offshore Gas Wells in the Arabian Gulf ». Dans SPE Middle East Oil & Gas Show and Conference. Society of Petroleum Engineers, 2017. http://dx.doi.org/10.2118/184004-ms.
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Alqunais, Ali, Charles Bradford et Khalid Qubaisi. « Integration of Cutting Spectroscopy Analysis and Open-Hole Logs to Increase Evaluation Certainty of Complex Clastic Formations – Advantages and Limitations ». Dans SPE Middle East Oil & Gas Show and Conference. SPE, 2021. http://dx.doi.org/10.2118/204693-ms.
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Abstract This paper presents an approach by integrating advanced cutting analysis, such as x-ray fluorescence (XRF), and open-hole logs for enhanced formation evaluation of complex clastic formations in near real-time. To verify the methodology, results of surface cuttings analyses are compared to and validated with downhole elemental spectroscopy measurements. In general, when the formation contains clays, the minimum logging requirement to evaluate clastic formations is a triple combo (density, neutron and resistivity) with spectral gamma ray (SGR) logs. In addition to correcting the impact of the drilling fluid additives and properties such as the presence of k-formate in mud, SGR logs become very crucial to differentiate clay types present in the formation. In the absence of SGR, advanced cuttings measurements can be utilized to provide elemental data of major elements including SGR components from the cuttings in near real-time. A comparison was made to evaluate the cuttings analysis as a replacement for SGR. As a part of this work and to validate the petrophysical evaluation results, downhole wireline SGR and elemental spectroscopy data were acquired and compared to the analysis using advanced cutting measurements. This work was conducted in a siliciclastic formation containing abrasive sandstones of mixed clean quartz and clay minerals. The analysis of cuttings XRF was integrated with basic downhole logs to quantify the clay typing required for representative formation evaluation and well geosteering. Limitations of this approach are identified in drilling complex clastic formations including cutting sampling frequency and effects of drilling including drilling fluid contamination, mud additives, drilling parameters and drilling driving mechanism. Controlling these factors has led to good results from cuttings measurements. The advanced cuttings XRF analysis was benchmarked with wireline SGR and elemental spectroscopy logs. This approach of using cuttings XRF analysis and basic open-hole logs is a valid option for geosteering in a complex clastic mineralogy formation and providing a near real-time formation evaluation in the absence of spectral gamma ray or elemental spectroscopy. XRF has been proven to provide near real-time analysis with improved reliability across bad hole, wider spectrum of elements and eliminate critical operations risk. Recommendations to optimize the parameters for reliable measurements will be discussed in this paper.
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Kalhor Mohammadi, Mojtaba, Shervin Taraghikhah, Mohammad Saeed Karimi Rad et Koroush Tahmasbi Nowtaraki. « Developing New Generation of Environmentally Friendly Nano Based Low Saline Water-Based Drilling Fluid ». Dans SPE/IADC Middle East Drilling Technology Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/202111-ms.
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Abstract Developing high-performance environmentally friendly drilling fluids is always a requirement by oil and gas operators to reduce the waste management associated cost with the drilling fluid treatment and disposal. Conventional water-based drilling fluid is formulated with the brine-based polymer which consists of sodium and potassium chloride salts to improve the performance of the polymer and also providing clay inhibition in reactive clay and shale. This paper describes the development of nanotechnology-based drilling fluid to replace salt from the conventional application. Nano Based Low Saline Water Based Mud (NBLS-WBM) was formulated and developed based on laboratory experiments. Different nano additives with different concentrations were evaluated and the optimum concentration was selected to reduce the sodium and potassium chloride salts concentration to almost zero. The rheological properties and fluid loss were measured according to the API standard before and after hot rolling. Also, HPHT fluid loss, lubricity, and shale inhibition were evaluated. All the results were compared with sodium salt-saturated and potassium-based polymer muds. Laboratory evaluation of NBLS-WBM indicated that sodium salt concentration can be reduced considerably up to 5% W/V and potassium chloride can be eliminated by adding 1% W/W of nano additive. The rheological properties including plastic viscosity and yield point were constant and stable after hot rolling 16 hours at 250 °F. Also, Clay inhibition improved significantly up to 95% recovery comparing with conventional water-based polymer mud. Although the application of nanotechnology to improve the performance of conventional water-based drilling fluid was studied by many researchers, it is the novelty of this research to reduce the salt concentration and remove it to develop the new generation of salt-free water-based drilling fluid with economical consideration and lower environmental impact.
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Khan, Rizwan Ahmed, Hafiz Mudaser Ahmad, Mobeen Murtaza, Abdulazeez Abdulraheem, Muhammad Shahzad Kamal et Mohamed Mahmoud. « Impact of Multi-Branched Ionic Liquid on Shale Swelling and Hydration for High Temperature Drilling Applications ». Dans SPE/IADC Middle East Drilling Technology Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/202143-ms.
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Abstract Shale swelling and hydration during the drilling operation have adverse effects on the stability of a wellbore. Hydrophilic interactions of shale results in swelling and disintegration of the shale formation. This paper discusses wettability changes and hydration characteristics of shale to improve the wellbore stability. The use of multibranched ionic liquid as drilling fluid for high temperature applications was investigated. The novel multibranched ionic liquid (Trihexyltetradecyl phosphonium bis (2,4,4-trimethyl pentyl) phosphinate, denoted as Tpb-P) water-based drilling fluid was prepared by mixing different concentrations of ionic liquid and other additives such as filtration controller, rheological modifier, and pH controller. The wettability of bentonite powder was determined using a contact angle in the presence of various concentrations of ionic liquids. Several other experimental techniques, such as linear swelling, hot rolling recovery, and bentonite swell index, were used to examine the inhibition performance of ionic liquid. The rheology and filtration properties of ionic liquid-based drilling fluid were also examined. Various concentrations of multibranched ionic liquid were used to formulate the drilling fluids ranging from (0.1 to 0.5 wt.%), and their performances were compared with the base drilling fluid prepared without ionic liquid. The hydrophobicity of the shale surface was determined by measuring the contact angle, and results showed that drilling fluid having 0.1 wt.% concentration of ionic liquid has a maximum contact angle indicating the highly hydrophobic shale surface. The hot rolling shale recovery experiment was conducted at 150°F, and it was observed that adding ionic liquid improved the shale recovery (24.4%) compared to the base fluid recovery (12.8%). The linear swelling was evaluated over the time of 24 hours, and the least swelling of bentonite was noticed with 0.1 wt.% ionic liquid (98.1%) compared to linear swelling in deionized water (125%). The results suggested that the ionic liquid in the drilling fluid chemically interacted with the clay surface and reduced the hydrophilicity of clay, which restricts the exchange of water onto the clay surface.
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Nugraha, Reza Satria, et Oliver Esteva Tumbarinu. « Enhancing Stratigraphic Framework Consistency Using Spectral Gamma-Ray Data ». Dans SPE Middle East Oil & Gas Show and Conference. SPE, 2021. http://dx.doi.org/10.2118/204836-ms.
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Abstract Stratigraphic correlation is crucial for reservoir characterization; therefore, it requires more advanced methods and techniques to reduce the stratigraphic correlation uncertainty, especially when variation in lateral facies is high. The studied formations from bottom to top consist of fluvial to marginal marine X Formation, shallow marine Y Formation, and fluvial distributary channels to estuarine Z Formation. Spectral gamma-ray logs give additional consistent information on lithological composition that can support identification of boundary between formations within the stratigraphic framework. Wells with a full section of Y Formation, core, palynology, and spectral gamma-ray were selected as key wells. The top and base of the Y Formation were picked using conventional logs refined by a thorium/potassium (Th/K) ratio log and cross plot with core and palynology data as validations. The internal Y Formation markers were also picked with the aid of the Th/K cross plots. The top picking criteria from the key wells was implemented to the rest of the wells across the field with consistency. The uniform low Th/K ratio log (<3.5) across the Y Formation indicates illite as the dominant clay type, confirmed by X-ray diffraction (XRD) data with an average of more than 80%. The character is consistent with the interpreted depositional environment. This character makes the Y Formation stand out from the overlying Z and the underlying X formations. The change from X to Y Formation is defined by the decrease of the Th/K ratio log, from high kaolinite content to illite dominated environment. Inversely, the top of the Y Formation (base of Z) is indicated by the increase of the Th/K ratio log moving from shallow marine Y Formation to the fluvial-influenced Z Formation. The Th/K cross plot indicates different clusters amongst the studied formations and the internal Y zonation. The X Formation is located in the high Th and low K area where kaolinite is predominant, related to fluvial environment. The case is similar for the Z Formation but with more influence of mixed-clay type. The Y Formation shows clear clustering along the mixed-clay and illite window. Internal Y zonation displays, from bottom to top, an increasing K value within the clusters. This method provides a semi-quantitative interpretation to define the studied formations boundaries and the Y Formation internal zonation. This study has increased the consistency of the studied formations’ stratigraphic and structural framework. This consistency has, in turn, fine-tuned the structural framework and aided field development through better geosteering and lateral well placements. These results are a valuable starting point to refine and extend the work to other areas.
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Fernández Palicio, Alejandro. « Urban vernacular architecture in the Middle Ages in Galicia, Spain ». Dans HERITAGE2022 International Conference on Vernacular Heritage : Culture, People and Sustainability. Valencia : Universitat Politècnica de València, 2022. http://dx.doi.org/10.4995/heritage2022.2022.15645.
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The emergence of the first urban settlements during the High Middle Ages in Galicia allowed the appearanceof a typology of half-timbered houses with very heterogeneous characteristics according to the differentGalician regions. Its general characteristics were a ground floor made of rammed earth, granite orschist stone and an upper floor made with a wooden framework system used as structural closures withdifferent fillings (clay, straw, stone, brick or decking). The urban fabric of these settlements has beenanalyzed, studying the survival of the medieval lots. A small number of half-timbered houses of medievalorigin have been found. The extension of this typology throughout the Galician geography allowed us torethink part of the existing imaginary about vernacular construction in Galicia and contextualize themedieval Galician urban phenomenon within the European context.
Rapports d'organisations sur le sujet "Middle Cla"
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Connell, Mary E., et Gregory Zalasky. CNA Workshop on Regional Issues : Russia, China and India : Strategic Interests in the Middle East. Organized by CNA for the U.S. Central Command. Fort Belvoir, VA : Defense Technical Information Center, septembre 2008. http://dx.doi.org/10.21236/ada487961.
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Shaver, R. M. X-ray diffraction clay analysis of Shell Western E & ; P Inc. Middle Ground Shoal (MGS) A-33-11 well. Alaska Division of Geological & Geophysical Surveys, 1986. http://dx.doi.org/10.14509/19209.
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Gall, Q. Diagenesis of Middle Proterozoic Basins, Churchill and Bear Provinces With Emphasis On Clay Mineralogy and Its Relation To Uranium Mineralization. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1992. http://dx.doi.org/10.4095/133344.
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Jackson, G. D. Bedrock geology, northwest part of Nuluujaak Mountain, Baffin Island, Nunavut, part of NTS 37-G/5. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/314670.
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The map area lies about 40 km northwest of Baffinland's iron mine. Dykes of unit mAnA3 within unit mAnA2 suggest that unit mAnA2 predates unit mAnA3. Unit nAMqf, basal Mary River Group unit, includes regolith material from units mAnA2 and mAnA3. Unit mAnAm may include some dykes of unit nAMb. The Mary River Group was deposited in a volcanic-arc environment, yielding zircon U-Pb ages mostly in the range of 2.88 to 2.72 Ga. Iron-formation (unit nAMi) is approximately 276 m thick locally, with oxide facies (unit nAMio) being most abundant. The quartzite triangle west of 'Iron lake' (unofficial name) may be a small horst. The main east-west-trending synclinal fold, including the area around 'Iron lake' and the no. 4 ore deposit, is upright, nearly isoclinal, and plunges mostly easterly at both ends with small scale anticlines and synclines in the middle. Magnetite constitutes about 75% of high-grade iron deposits in the north limb, whereas hematite predominates in south-limb deposits. K-Ar and Rb-Sr ages indicate middle Paleoproterozoic overprinting. Central Borden Fault Zone was active at ca. 1.27 Ga and during or after Ordovician time. Note: please be aware that the information contained in CGM 408 is based on legacy data from the 1960-1990s and that it has been superseded by regional-scale information contained in CGM 403.
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Foscolos, A. E. Mass Transfer of Elements in Middle Triassic Shale / Sandstone Sequences, Sverdrup Basin, Arctic Islands, Part 2 : Mineralogy, Clay Mineralogy, Thermogravimetric Analysis and Chemistry of the Greater Than .2 Micron Fraction and Sem Studies On Thin Sections, East Drake L-06 and Sky Battle Bay M-11 Cores. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1989. http://dx.doi.org/10.4095/130812.
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Shomer, Ilan, Ruth E. Stark, Victor Gaba et James D. Batteas. Understanding the hardening syndrome of potato (Solanum tuberosum L.) tuber tissue to eliminate textural defects in fresh and fresh-peeled/cut products. United States Department of Agriculture, novembre 2002. http://dx.doi.org/10.32747/2002.7587238.bard.
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The project sought to understand factors and mechanisms involved in the hardening of potato tubers. This syndrome inhibits heat softening due to intercellular adhesion (ICA) strengthening, compromising the marketing of industrially processed potatoes, particularly fresh peeled-cut or frozen tubers. However, ICA strengthening occurs under conditions which are inconsistent with the current ideas that relate it to Ca-pectate following pectin methyl esterase (PME) activity or to formation of rhamnogalacturonan (RG)-II-borate. First, it was necessary to induce strengthening of the middle lamellar complex (MLX) and the ICA as a stress response in some plant parenchyma. As normally this syndrome does not occur uniformly enough to study it, we devised an efficient model in which ICA-strengthening is induced consistently under simulated stress by short-chain, linear, mono-carboxylic acid molecules (OAM), at 65 oC [appendix 1 (Shomer&Kaaber, 2006)]. This rapid strengthening was insufficient for allowing the involved agents assembly to be identifiable; but it enabled us to develop an efficient in vitro system on potato tuber parenchyma slices at 25 ºC for 7 days, whereas unified stress was reliably simulated by OAMs in all the tissue cells. Such consistent ICA-strengthening in vitro was found to be induced according to the unique physicochemical features of each OAM as related to its lipophilicity (Ko/w), pKa, protonated proportion, and carbon chain length by the following parameters: OAM dissociation constant (Kdiss), adsorption affinity constant (KA), number of adsorbed OAMs required for ICA response (cooperativity factor) and the water-induced ICA (ICAwater). Notably, ICA-strengthening is accompanied by cell sap leakage, reflecting cell membrane rupture. In vitro, stress simulation by OAMs at pH<pKa facilitated the consistent assembly of ICAstrengthening agents, which we were able to characterize for the first time at the molecular level within purified insoluble cell wall of ICA-strengthened tissue. (a) With solid-state NMR, we established the chemical structure and covalent binding to cell walls of suberin-like agents associated exclusively with ICA strengthening [appendix 3 (Yu et al., 2006)]; (b) Using proteomics, 8 isoforms of cell wall-bound patatin (a soluble vacuolar 42-kDa protein) were identified exclusively in ICA-strengthened tissue; (c) With light/electron microscopy, ultrastructural characterization, histochemistry and immunolabeling, we co-localized patatin and pectin in the primary cell wall and prominently in the MLX; (d) determination of cell wall composition (pectin, neutral sugars, Ca-pectate) yielded similar results in both controls and ICA-strengthened tissue, implicating factors other than PME activity, Ca2+ or borate ions; (e) X-ray powder diffraction experiments revealed that the cellulose crystallinity in the cell wall is masked by pectin and neutral sugars (mainly galactan), whereas heat or enzymatic pectin degradation exposed the crystalline cellulose structure. Thus, we found that exclusively in ICA-strengthened tissue, heat-resistant pectin is evident in the presence of patatin and suberinlike agents, where the cellulose crystallinity was more hidden than in fresh control tissue. Conclusions: Stress response ICA-strengthening is simulated consistently by OAMs at pH< pKa, although PME and formation of Ca-pectate and RG-II-borate are inhibited. By contrast, at pH>pKa and particularly at pH 7, ICA-strengthening is mostly inhibited, although PME activity and formation of Ca-pectate or RG-II-borate are known to be facilitated. We found that upon stress, vacuolar patatin is released with cell sap leakage, allowing the patatin to associate with the pectin in both the primary cell wall and the MLX. The stress response also includes formation of covalently bound suberin-like polyesters within the insoluble cell wall. The experiments validated the hypotheses, thus led to a novel picture of the structural and molecular alterations responsible for the textural behavior of potato tuber. These findings represent a breakthrough towards understanding of the hardening syndrome, laying the groundwork for potato-handling strategies that assure textural quality of industrially processed particularly in fresh peeled cut tubers, ready-to-prepare and frozen preserved products.
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Rahmani, Mehran, Xintong Ji et Sovann Reach Kiet. Damage Detection and Damage Localization in Bridges with Low-Density Instrumentations Using the Wave-Method : Application to a Shake-Table Tested Bridge. Mineta Transportation Institute, septembre 2022. http://dx.doi.org/10.31979/mti.2022.2033.
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This study presents a major development to the wave method, a methodology used for structural identification and monitoring. The research team tested the method for use in structural damage detection and damage localization in bridges, the latter being a challenging task. The main goal was to assess capability of the improved method by applying it to a shake-table-tested prototype bridge with sparse instrumentation. The bridge was a 4-span reinforced concrete structure comprising two columns at each bent (6 columns total) and a flat slab. It was tested to failure using seven biaxial excitations at its base. Availability of a robust and verified method, which can work with sparse recording stations, can be valuable for detecting damage in bridges soon after an earthquake. The proposed method in this study includes estimating the shear (cS) and the longitudinal (cL) wave velocities by fitting an equivalent uniform Timoshenko beam model in impulse response functions of the recorded acceleration response. The identification algorithm is enhanced by adding the model’s damping ratio to the unknown parameters, as well as performing the identification for a range of initial values to avoid early convergence to a local minimum. Finally, the research team detect damage in the bridge columns by monitoring trends in the identified shear wave velocities from one damaging event to another. A comprehensive comparison between the reductions in shear wave velocities and the actual observed damages in the bridge columns is presented. The results revealed that the reduction of cS is generally consistent with the observed distribution and severity of damage during each biaxial motion. At bents 1 and 3, cS is consistently reduced with the progression of damage. The trends correctly detected the onset of damage at bent 1 during biaxial 3, and damage in bent 3 during biaxial 4. The most significant reduction was caused by the last two biaxial motions in bents 1 and 3, also consistent with the surveyed damage. In bent 2 (middle bent), the reduction trend in cS was relatively minor, correctly showing minor damage at this bent. Based on these findings, the team concluded that the enhanced wave method presented in this study was capable of detecting damage in the bridge and identifying the location of the most severe damage. The proposed methodology is a fast and inexpensive tool for real-time or near real-time damage detection and localization in similar bridges, especially those with sparsely deployed accelerometers.
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Michelmore, Richard, Eviatar Nevo, Abraham Korol et Tzion Fahima. Genetic Diversity at Resistance Gene Clusters in Wild Populations of Lactuca. United States Department of Agriculture, février 2000. http://dx.doi.org/10.32747/2000.7573075.bard.
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Genetic resistance is often the least expensive, most effective, and ecologically-sound method of disease control. It is becoming apparent that plant genomes contain large numbers of disease resistance genes. However, the numbers of different resistance specificities within a genepool and the genetic mechanisms generating diversity are poorly understood. Our objectives were to characterize diversity in clusters of resistance genes in wild progenitors of cultivated lettuce in Israel and California in comparison to diversity within cultivated lettuce, and to determine the extent of gene flow, recombination, and genetic instability in generating variation within clusters of resistance genes. Genetic diversity of resistance genes was analyzed in wild and cultivated germplasm using molecular markers derived from lettuce resistance gene sequences of the NBS-LRR type that mapped to the major cluster if resistance genes in lettuce (Sicard et al. 1999). Three molecular markers, one microsatellite marker and two SCAR markers that amplified LRR- encoding regions, were developed from sequences of resistance gene homologs at the Dm3 cluster (RGC2s) in lettuce. Variation for these markers was assessed in germplasm including 74 genotypes of cultivated lettuce, L. saliva and 71 accessions of the three wild Lactuca spp., L. serriola, L. saligna and L. virosa that represent the major species in the sexually accessible genepool for lettuce. Diversity was also studied within and between natural populations of L. serriola from Israel and California. Large numbers of haplotypes were detected indicating the presence of numerous resistance genes in wild species. We documented a variety of genetic events occurring at clusters of resistance genes for the second objective (Sicard et al., 1999; Woo el al., in prep; Kuang et al., in prepb). The diversity of resistance genes in haplotypes provided evidence for gene duplication and unequal crossing over during the evolution of this cluster of resistance genes. Comparison of nine resistance genes in cv. Diana identified 22 gene conversion and five intergenic recombinations. We cloned and sequenced a 700 bp region from the middle of RGC2 genes from six genotypes, two each from L. saliva, L. serriola, and L. saligna . We have identified over 60 unique RGC2 sequences. Phylogenetic analysis surprisingly demonstrated much greater similarity between than within genotypes. This led to the realization that resistance genes are evolving much slower than had previously been assumed and to a new model as to how resistance genes are evolving (Michelmore and Meyers, 1998). The genetic structure of L. serriola was studied using 319 AFLP markers (Kuang et al., in prepa). Forty-one populations from Turkey, Armenia, Israel, and California as well as seven European countries were examined. AFLP marker data showed that the Turkish and Armenian populations were the most polymorphic populations and the European populations were the least. The Davis, CA population, a recent post-Columbian colonization, showed medium genetic diversity and was genetically close to the Turkish populations. Our results suggest that Turkey - Armenia may be the center of origin and diversity of L. serriola and may therefore have the greatest diversity of resistance genes. Our characterization of the diversity of resistance genes and the genetic mechanisms generating it will allow informed exploration, in situ and ex situ conservation, and utilization of germplasm resources for disease control. The results of this project provide the basis for our future research work, which will lead to a detailed understanding of the evolution of resistance genes in plants.
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Composition, clay mineralogy, and diagenesis of the Simpson Group (Middle Ordovician), Grady County, Oklahoma. US Geological Survey, 1991. http://dx.doi.org/10.3133/b1866h.
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Chapter I : Geology of a Middle Tertiary Clay Deposit in thePatagonia Mountains near Harshaw, Santa Cruz County, Southeastern Arizona. US Geological Survey, 2005. http://dx.doi.org/10.3133/b2209i.
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