768 resultados para disappearance
Resumo:
Este ensayo examina el rol del concepto de discurso en la génesis de la teoría de los Aparatos Ideológicos de Estado (AIE) de Althusser. Una lectura de sus "Tres notas sobre la teoría de los discursos" sugiere que la práctica desaparición del término "discurso" de ensayo sobre los AIE representa la supresión y no la resolución de las tensiones que afectan a la noción de la interpelación del sujeto. Al leer a Althusser a la luz de la teoría spinociana del decreto, desarrollada en la Ética, y de la noción de discurso de Pêcheux, nos tornamos capaces de aprehender la materialidad del lenguaje en todos sus aspectos, pero también de reformular el vocabulario de la conciencia y la interioridad de una manera materialista. La conjunción de Spinoza, Althusser y Pêcheux nos permite comprender mejor y transformar mediante la lucha lo que el último denominó "la peste de la sujeción".
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The last glacial-interglacial transition or Termination I (T I) is well documented in the Black Sea, whereas little is known about climate and environmental dynamics during the penultimate Termination (T II). Here we present a multi-proxy study based on a sediment core from the SE Black Sea covering the penultimate glacial and almost the entire Eemian interglacial (133.5 ±0.7-122.5 ±1.7 ka BP). Proxies comprise ice-rafted debris (IRD), O and Sr isotopes as well as Sr/Ca, Mg/Ca, and U/Ca ratios of benthic ostracods, organic and inorganic sediment geochemistry, as well as TEX86 and UK'37derived water temperatures. The ending penultimate glacial (MIS 6, 133.5 to 129.9 ±0.7 ka BP) is characterised by mean annual lake surface temperatures of about 9°C as estimated from the TEX86 palaeothermometer. This period is impacted by two Black Sea melt water pulses (BSWP-II-1 and 2) as indicated by very low Sr/Ca ostracods but high sedimentary K/Al values. Anomalously high radiogenic 87Sr/86Sr ostracod values (max. 0.70945) during BSWP-II-2 suggest a potential Himalayan source communicated via the Caspian Sea. The T II warming started at 129.9 ±0.7 ka BP, witnessed by abrupt disappearance of IRD, increasing d18O ostracod values, and a first TEX86 derived temperature rise of about 2.5°C. A second, abrupt warming step to ca. 15.5°C as the prelude of the Eemian warm period is documented at 128.3 ka BP. The Mediterranean-Black Sea reconnection most likely occurred at 128.1 ±0.7 ka BP as demonstrated by increasing Sr/Ca ostracods and U/Ca ostracods values. The disappearance of ostracods and TOC contents >2% document the onset of Eemian sapropel formation at 127.6 ka BP. During sapropel formation, TEX86 temperatures dropped and stabilised at around 9°C, while UK'37 temperatures remain on average 17°C. This difference is possibly caused by a habitat shift of Thaumarchaeota communities from surface towards nutrient-rich deeper and colder waters located above the gradually establishing halo-and redoxcline.
Resumo:
The pulsed decline and eventual extinction of 51 species of elongate, cylindrical deep-sea benthic foraminifera (Stilostomellidae, Pleurostomellidae, and some Nodosariidae) occurred at intermediate water depths (1145-2168 m, Sites 980 and 982) in the northern North Atlantic during the mid-Pleistocene transition (MPT, 1.2-0.6 Ma). In the early Pleistocene, prior to their disappearance, these species comprised up to 20% of the total abundance of the benthic foraminiferal assemblage at 2168 m, but up to only 2% at 1145 m. The MPT extinction of 51 species represents ?20% of the total benthic foraminiferal diversity at bathyal depths in the North Atlantic (excluding the myriad of small unilocular forms). The extinction rate during the MPT was approximately 10 species per 0.1 myr, being one or two orders of magnitude greater than normal background turnover rates of deep-sea benthic foraminifera. Comparison of the precise timings of declines and disappearances (= highest occurrences) of each species shows that they were often diachronous between the two depths. The last of these species to disappear in the North Atlantic was Pleurostomella alternans at ~0.679 and ~0.694 Ma in Sites 980 and 982, respectively, which is in good agreement with the previously documented global "Stilostomella extinction" datum within the period 0.7-0.58 Ma. Comparison with similar studies in intermediate depth waters in the Southwest Pacific Gateway indicates that ~61% of the extinct species were common to both regions, and that although the pattern of pulsed decline was similar, the precise order and timing of the extinction of individual species were mostly different on opposite sides of the world. Previous studies have indicated that this extinct group of elongate, cylindrical foraminifera lived infaunally and had their greatest abundances in poorly ventilated, lower oxygen environments. This is supported by our study where there is a strong positive correlation (r = ~+ 0.8) between the flux of the extinction group and low-oxygen/high organic input species (such as Uvigerina, Bulimina and Bolivina) during the MPT, suggesting a close relationship with lower oxygen levels and high food supply to the sea floor. The absolute abundance, flux, and number of the extinction group of species show a progressive withdrawal pattern with major decreases occurring in cold periods with high d13C values. This might be related to increasing chemical ventilation of glacial intermediate water.
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Peroxide-mediated reactive extrusion of linear isotactic polypropylene (L-PP) was conducted in the presence of trimethylolpropane trimethacrylate (TMPTMA) and triallyl trimesate (TAM) coagents, using a twin screw extruder. The resulting coagent-modified polypropylenes (CM-PP) had higher viscosities and elasticities, as well as increased crystallization temperature compared to PP reacted only with peroxide (DCP-PP). Additionally, deviations from terminal flow, and strain hardening were observed in PP modified with TAM, signifying the presence of long chain branching (LCB). The CM-PP formulations retained the modulus and tensile strength of the parent L-PP, in spite of their lower molar mass and viscosities, whereas their elongation at break and the impact strength were better. This was attributed to the finer spherulitic structure of these materials, and to the disappearance of the skin-core layer in the injection molded specimens.
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Durante el siglo XIII se produjo una sucesión de revueltas que supuso la desaparición del Imperio almohade y su sustitución por poderes regionales en al-Andalus, el Magreb y el Magreb al-Aqsà. La historiografía ha presentado el surgimiento y pugna entre estos poderes como un fenómeno social, político e, incluso, cultural y religioso, con el que se ha podido explicar su aniquilación o marginalización. Este trabajo pretende contextualizar los hechos desde una perspectiva medioambiental, de forma que la desintegración del califato almohade, el surgimiento de aquellos poderes y la progresión de los reinos cristianos en la península ibérica puedan entenderse desde una visión global de cambio climático y una posible crisis agrícola.
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Glacier and ice sheet retreat exposes freshly deglaciated terrain which often contains small-scale fragile geomorphological features which could provide insight into subglacial or submarginal processes. Subaerial exposure results in potentially rapid landscape modification or even disappearance of the minor–relief landforms as wind, weather, water and vegetation impacts on the newly exposed surface. Ongoing retreat of many ice masses means there is a growing opportunity to obtain high resolution geospatial data from glacier forelands to aid in the understanding of recent subglacial and submarginal processes. Here we used an unmanned aerial vehicle to capture close-range aerial photography of the foreland of Isfallsglaciären, a small polythermal glacier situated in Swedish Lapland. An orthophoto and a digital elevation model with ~2 cm horizontal resolution were created from this photography using structure from motion software. These geospatial data was used to create a geomorphological map of the foreland, documenting moraines, fans, channels and flutes. The unprecedented resolution of the data enabled us to derive morphological metrics (length, width and relief) of the smallest flutes, which is not possible with other data products normally used for glacial landform metrics mapping. The map and flute metrics compare well with previous studies, highlighting the potential of this technique for rapidly documenting glacier foreland geomorphology at an unprecedented scale and resolution. The vast majority of flutes were found to have an associated stoss-side boulder, with the remainder having a likely explanation for boulder absence (burial or erosion). Furthermore, the size of this boulder was found to strongly correlate with the width and relief of the lee-side flute. This is consistent with the lee-side cavity infill model of flute formation. Whether this model is applicable to all flutes, or multiple mechanisms are required, awaits further study.
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Despite a rich body of research on the conflict and peace process in Northern Ireland, the ‘disappearances’ carried out by Republican armed groups have so far escaped scrutiny. In this article I examine how the Republican movement has framed the rationale behind ‘disappearing’ as a rational response to informing and as an example of historical continuity. In doing so, Republicans appear to attempt to confer legitimacy on their choice of target and normalize the use of the practice within a Republican framework. However, these rationales incorporate techniques of neutralization and attempts to contextualize the ‘disappearances’ in such a way as to distance the Irish Republican Army from agency. Such distancing speaks to a third, overarching rationale for ‘disappearing’: the avoidance of an embarrassment that has continued into the postconflict period. I consider why Republicans persist in claiming the ‘disappeared’ were legitimate targets, killed by a method for which there is historical precedent, when such framing left them open to criticism at a time when they were seeking to demonstrate that they had left violence behind. I conclude that Republican attempts to satisfy two audiences resulted in a gulf between their engagement in the process of recovering remains and their rhetoric surrounding this issue. In so doing, light is shed on some of the challenges the Republican movement faced in their transition away from violence. More broadly, the value of unpicking the framing of key actors in transitional processes is illuminated.
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Graphene with heteroatom doping has found increasing applications in a broad range of catalytic reactions. However, the doping effects accounting for the enhanced catalytic activity still remain elusive. In this work, taking the triiodide electroreduction reaction as an example, we study systematically the intrinsic activity of graphene and explore the origin of doping-induced activity variation using first-principles calculations, in which two typical N and S dopants are tested. The most common graphene structures, basal plane, armchair edge, and zigzag edge, are considered, and it is found that the former two structures show a weak adsorption ability for the iodine atom (the key intermediate in the triiodide electroreduction reaction), corresponding to a low catalytic activity. Doping either N or S can strengthen the adsorption and thus increase the activity, and the codoping of N and S (NS-G) exhibits a synergistic effect. A detailed investigation into the whole process of the triiodide electroreduction reaction at the CH3CN/NS-G interface is also carried out to verify these activity trends. It is found that the zigzag edges which contain spin electrons show a relatively stronger adsorption strength compared with the basal plane and armchair edge, and initial doping would result in the spin disappearance that evidently weakens the adsorption; with the disappearance of spin, however, further doping can increase the adsorption again, suggesting that the spin electrons may play a preliminary role in affecting the intrinsic activity of graphene. We also analyzed extensively the origin of doping-induced adsorption enhancement of graphene in the absence of spin; it can be rationalized from the electronic and geometric factors. Specifically, N doping can result in a more delocalized “electron-donating area” to enhance I adsorption, while S doping provides a localized structural distortion, which activates the nearest sp2-C into coordinatively unsaturated sp3-C. These results explain well the improved activity of the doping and the synergistic effect of the codoping. The understandings are generalized to provide insight into the enhanced activity of the oxygen reduction reaction on heteroatom doped graphene. This work may be of importance toward the design of high-activity graphene based material.
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The turn of the twenty-first century witnessed a surprising reversal of the long-observed trend towards the disappearance of second chambers in unitary states, with 28 countries – all but one of them unitary – adopting the bicameral system. This article explores this development by first setting it in the context of the historical evolution of second chambers and the arguments that support bicameralism, and then exploring the characteristics that distinguish today’s second chambers from first chambers. A ‘census’ of second chambers in 2014 is used to provide data on second chambers in federal and unitary states, to facilitate comparison with earlier data, and to distinguish between ‘new’ and longer-established second chambers. The article concludes that newly established second chambers are concentrated predominantly in political systems where liberal democratic principles are not established, suggesting that the debate over their role in democratic states is set to continue.
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Tubular function of 17 pediatric patients with a mild form of acute post-infectious glomerulonephritis was prospectively evaluated by assessment of the urinary activity of proximal and distal tubule enzymes. Neutral-like endopeptidase (NEP-like) and angiotensin-converting enzyme (ACE) were the proximal tubule enzymes assessed, while prolyl-endopeptidase (PE) and serine-endopeptidase H1 and H2 were the distal tubule enzymes analyzed. Urine was collected at diagnosis (T0) and after 2 (T2) and 6 (T6) months of follow-up. NEP-like enzyme activity (nmol/mg creatinine; median±quartile range) was increased at diagnosis, and this remained stable during the first 6 months (T0 18.30±83.26, T2 17.32±49.56, T6 23.38±107.18). Urinary activity of the other enzymes was as follows: ACE (mU/ml per mg creatinine) T0 0.08±0.16, T2 0.06±0.10, T6 0.18±0.29; PE (nmol/mg creatinine) T0 6.70±84.87, T2 9.55±69.00, T6 13.67±28.70; serine-endopeptidase H1 (nmol/mg creatinine) T0 7.86±26.95, T2 17.17±59.37, T6 18.19± 79.14; and serine-thiol-endopeptidase H2 (nmol/mg creatinine) T0 3.06±21.97, T2 12.06±32.42, T6 16.22± 44.06. Thirty other healthy children matched for age and gender were considered as a control group. This group was assessed once and the results were: NEP-like activity 6.05±10.54, ACE 0.11±0.22, PE 7.10±13.36, H1 5.00±17.30, and H2 6.00±20.16. In conclusion, we observed that NEP-like and H1 enzymes exhibited significant increased urinary activity 6 months after the diagnosis. This increase occurred in spite of the disappearance of clinical symptoms, which occurred 2 months after the diagnosis. We believe that the increase in urinary enzymatic activity could be a manifestation of a silent tubular dysfunction following an episode of acute post-infectious glomerulonephritis.
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A history of specialties in economics since the late 1950s is constructed on the basis of a large corpus of documents from economics journals. The production of this history relies on a combination of algorithmic methods that avoid subjective assessments of the boundaries of specialties: bibliographic coupling, automated community detection in dynamic networks, and text mining. These methods uncover a structuring of economics around recognizable specialties with some significant changes over the period covered (1956–2014). Among our results, especially noteworthy are (1) the clear-cut existence of ten families of specialties, (2) the disappearance in the late 1970s of a specialty focused on general economic theory, (3) the dispersal of the econometrics-centered specialty in the early 1990s and the ensuing importance of specific econometric methods for the identity of many specialties since the 1990s, and (4) the low level of specialization of individual economists throughout the period in contrast to physicists as early as the late 1960s.
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Cette thèse considère les suites de la paix d’Apamée sur le plan des relations politiques entre les États d’Anatolie et sur l’évolution de la place tenue par cette péninsule dans l’ordre géopolitique méditerranéen. Le traité d’Apamée, conclu en 188 avant notre ère entre la puissance romaine et le royaume séleucide, fut un acte diplomatique majeur pour l’Asie Mineure et l’ensemble de la région anatolienne, libérés de la domination des Séleucides. Jusqu’ici, l’historiographie traditionnelle a abordé ce sujet selon deux perspectives, à savoir l’apparition de l’impérialisme romain en Orient et la vie politique et administrative des cités égéennes. À l’inverse, cette étude se concentre sur les principales puissances politiques de la région anatolienne : les royaumes. Dans le cadre de cet espace fragmenté et diversifié, des modifications de l’équilibre géopolitique régional peuvent être mises en relation avec le bouleversement de l’ordre méditerranéen, par le croisement de sources grecques, latines et orientales, ainsi qu’en faisant usage de procédés développés par le courant de la World History. L’évolution ultérieure de la situation mise en place à Apamée est étudiée jusqu’au point de disparition d’une Anatolie dirigée par des souverains non incorporés dans l’horizon impérial des grandes puissances étrangères, situation à laquelle les ultimes défaites de Mithridate VI du Pont et de Tigrane d’Arménie face à Rome mirent un terme définitif.
Resumo:
A sociedade está espontaneamente em constante transformação e isso reflete-se na cultura de um povo e no artesanato, sendo primordial o desenvolvimento de produtos que acompanhem essa mudança. O artesanato insere-se de forma natural em ambientes locais, absorvendo e caracterizando a cultura e identidade de uma região, contudo com o passar do tempo tem havido uma deterioração cultural, levando à desvalorização do artesanato e até ao desaparecimento de identidades culturais, de saberes e artes ancestrais. O presente projeto tem como objetivo a valorização e readaptação do Cobertor de Papa, um produto artesanal fabricado exclusivamente na Guarda, através da simbiose entre o design e o artesanato. O design tem vindo a afirmar-se com uma mais-valia, ou seja um instrumento imprescindível para a afirmação do artesanato. Esta ligação entre o design e o artesanato é vital para a preservação e revitalização das técnicas e saberes obsoletos, assim como para o desenvolvimento de produtos contemporâneos, impregnados de memórias e cultura, mas que respondem às necessidades da sociedade atual. É o saber e a técnica do artesão conexo com a criatividade e inovação do design, que diferencia estes produtos dos produtos industriais, massificados, sem identidade, tornandoos únicos, especiais e próprios. Pretende-se assim criar novos produtos, com base no Cobertor de Papa, salvaguardando a produção artesanal, as raízes culturais deste povo, através dos caminhos da inovação e criatividade. Evidenciando sempre a valorização, a preservação e revitalização das técnicas utilizadas nesta arte e transmitindo os conhecimentos para que estes não se percam no tempo. Há uma intensão de ajudar a posicionar o Cobertor de Papa no mercado atual, satisfazendo as necessidades da sociedade e do consumidor vigente, com o intuito de enaltecer esta arte, bem como as suas estirpes e essência.
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Pelvic organ prolapse suspension (POPS) is a recent surgical procedure for one-stage treatment of multiorgan female pelvic prolapse. This study evaluates the preliminary results of laparoscopic POPS in 54 women with a mean age of 55.2 and a BMI of 28.3. Patients underwent at the same time stapled transanal rectal resection (STARR) to correct the residual rectal prolapse. We had no relapses and the preliminary results were excellent. We evaluated the patients after 1 year follow-up and we confirmed the validity of our treatment. The technique is simplier than traditional treatments with an important reduction or completely disappearance of the pre-operative symptomatology.
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During 2012-2013, the homicide rate in El Salvador came down from 69.9 to 42.2 per 100,000 population following a truce between the leaders of the two major gangs, “Mara Salvatrucha” and “Barrio 18”, and government. But despite the apparent successes of the truce, it was speculated that the drop in murders could have been due to the killers simply hid the bodies of their victims. This paper aims at determining whether gangs effectively disappeared their victims to cut down the official counts of murders, or they committed these crimes for other reasons. The results from this study suggest that Salvadoran gangs had been using disappearance as a resource to gain sustained social control among residents of already gang-dominated areas, that together with homicide, disappearance is part of a process of territorial spread and strategic strengthening by which these groups are enhancing their capabilities to interfere in the alliances of Mexican drug trafficking organizations with Central American criminal organizations specializing in the transshipment of drugs and in providing access to local markets to distribute and sell drugs. Our findings show that the risk for disappearance has been large even before the truce was in place and that actually, it continues as such and going through a process of geographic expansion.