958 resultados para position change
Resumo:
BACKGROUND: A key aspect of representations for object recognition and scene analysis in the ventral visual stream is the spatial frame of reference, be it a viewer-centered, object-centered, or scene-based coordinate system. Coordinate transforms from retinocentric space to other reference frames involve combining neural visual responses with extraretinal postural information. METHODOLOGY/PRINCIPAL FINDINGS: We examined whether such spatial information is available to anterior inferotemporal (AIT) neurons in the macaque monkey by measuring the effect of eye position on responses to a set of simple 2D shapes. We report, for the first time, a significant eye position effect in over 40% of recorded neurons with small gaze angle shifts from central fixation. Although eye position modulates responses, it does not change shape selectivity. CONCLUSIONS/SIGNIFICANCE: These data demonstrate that spatial information is available in AIT for the representation of objects and scenes within a non-retinocentric frame of reference. More generally, the availability of spatial information in AIT calls into questions the classic dichotomy in visual processing that associates object shape processing with ventral structures such as AIT but places spatial processing in a separate anatomical stream projecting to dorsal structures.
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This paper will focus on three episodes of contemporary church-state relations in Georgia, in particular, the conflicting interaction between law and religion in the public space. The first episode will be an open confrontation between the church and the state over the law on Registration of Religious Minority organizations (2011) which allowed the religious minorities to freely register; second: the Law on Self-governance (2013) which Georgian Orthodox Church considered “a threat to territorial integrity of Georgia”; and lastly: the Law on Anti-discrimination (2014) which was deemed “legitimization of Sodomic sin”. By reflecting on the three examples where for the first time after the collapse of Soviet Union, the Georgian state openly confronted the church and made a decision notwithstanding its position, I will attempt to argue that the role of the Orthodox Church in influencing the law making process is in gradual decline. However, on the other hand, by presenting the results of an ethnographic study conducted in 23 eparchies and perishes in 7 regions of Georgia in 2014, I will also show that church has adapted to its declining role over policy making, and to regain its political influence it gradually started to employ a civic rather than ethno nationalist discourse on matters of religious freedom while engaging with government. The paper will suggest that both unilateral decision-making of the state and civic shift in the discourse of the church constitute an important change in understanding church-state dynamics in the post-communist Orthodox Christianity dominated society.
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Gender-fair language (GFL) is a symmetric linguistic treatment of women and men. To create GFL two principle strategies can be deployed. Neutralization means that gender-unmarked forms (police officer) are used to substitute the male-biased (policeman). Feminization, implies that feminine forms of nouns are used systematically to make female referents visible. The results of a comprehensive European research program provide evidence in support of a non-discrimination policy in language, yet identify the potential setbacks preventing linguistic reforms to be effective. In general, studies indicate positive effects of GFL. In an applied context, for example women feel more motivated to apply for the position if a job advertisement is formulated in a GFL. However, negative effects of reformed usage were also reported specifically when GFL is novel. For example, a woman referred to as a chairperson was evaluated lower in occupational status than a woman referred to as a chairman.
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An astronomically calibrated timescale has recently been established [Hilgen, 1991, doi:10.1016/0012-821X(91)90082-S; doi:10.1016/0012-821X(91)90206-W] for the Pliocene and earliest Pleistocene based on the correlation of dominantly precession controlled sedimentary cycles (sapropels and carbonate cycles) in Mediterranean marine sequences to the precession time series of the astronomical solution of Berger and Loutre [1991, doi:10.1016/0277-3791(91)90033-Q ] (hereinafter referred to as Ber90). Here we evaluate the accuracy of this timescale by (1) comparing the sedimentary cycle patterns with 65°N summer insolation time series of different astronomical solutions and (2) a cross-spectral comparison between the obliquity-related components in the 65°N summer insolation curves and high-resolution paleoclimatic records derived from the same sections used to construct the timescale. Our results show that the carbonate cycles older than 3.5 m.y. should be calibrated to one precession cycle older than previously proposed. Application of the astronomical solution of Laskar [1990, doi:10.1016/0019-1035(90)90084-M], (hereinafter referred to as La90) with present-day values for the dynamical ellipticity of the Earth and tidal dissipation by the Sun and Moon results in the best fit with the geological record, indicating that this solution is the most accurate from a geological point of view. Application of Ber90, or La90 solutions with dynamical ellipticity values smaller or larger than the present-day value, results in a less obvious fit with the geological record. This implies that the change in the planetary shape of the Earth associated with ice loading and unloading near the poles during the last 5.3 million years was too small to drive the precession into resonance with the perturbation term, s6-g6+g5, of Jupiter and Saturn. Our new timescale results in a slight but significant modification of all ages of the sedimentary cycles, bioevents, reversal boundaries, chronostratigraphic boundaries, and glacial cycles. Moreover, a comparison of this timescale with the astronomical timescales of ODP site 846 [Shackleton et al., 1995, doi:10.2973/odp.proc.sr.138.106.1995; doi:10.2973/odp.proc.sr.138.117.1995] and ODP site 659 [Tiedemann et al., 1994, doi:10.1029/94PA00208] indicates that all obliquity-related glacial cycles prior to ~4.7 Ma in ODP sites 659 and 846 should be correlated with one obliquity cycle older than previously proposed.
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The main motivation for Integrated Ocean Drilling Program Expedition 310 to the Tahitian Archipelago was the assumption that the last deglacial sea-level rise is precisely recorded in the coral reefs of this far-field site. The Tahitian deglacial succession typically consists of coral framework subsequently encrusted by coralline algae and microbialites. The high abundance of microbialites is uncommon for shallow-water coral reefs, and the environmental conditions favouring their development are still poorly understood. Microbioerosion patterns in the three principal framework components (corals, coralline algae, microbialites) are studied with respect to relative light availability during coral growth and subsequent encrustation, in order to constrain the palaeobathymetry and the relative timing of the encrustation. Unexpectedly for a tropical, light-flooded setting, ichnotaxa typical for the deep-euphotic to dysphotic zone dominate. The key ichnotaxa for the shallow euphotic zone are scarce in the analysed sample set, and are restricted tothe baseof thedeglacial succession, thus reflecting thedeglacial sea-level rise. At the base of the deglacial reef succession, the ichnocoenoses present in the corals indicate shallower bathymetries than those in the encrusting microbialites. This is in agreement with radiocarbon data that indicate a time gap of more than 600 years between coral death and microbialite formation. At the top of the deglacial reef succession, in contrast, the microbioerosion patterns in the three framework components indicate a uniform palaeobathymetry, and radiocarbon ages imply that encrustation took place shortly after coral demise. An enigma arises from the fact that the ichnocoenoses imply photic conditions that appear very deep for zooxanthellate coral growth. During the deglacial sea-level rise increased nutrients and fluvial influx may have led to (seasonal?) eutrophication, condensing the photic zonation. This would have exerted stress on the coral ecosystem and played a significant role in initiating microbialite development.
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There is evidence that the climate changes and that now, the change is influenced and accelerated by the CO2 augmentation in atmosphere due to combustion by humans. Such ?Climate change? is on the policy agenda at the global level, with the aim of understanding and reducing its causes and to mitigate its consequences. In most countries and international organisms UNO (e.g. Rio de Janeiro 1992), OECD, EC, etc . . . the efforts and debates have been directed to know the possible causes, to predict the future evolution of some variable conditioners, and trying to make studies to fight against the effects or to delay the negative evolution of such. The Protocol of Kyoto 1997 set international efforts about CO2 emissions, but it was partial and not followed e.g. by USA and China . . . , and in Durban 2011 the ineffectiveness of humanity on such global real challenges was set as evident. Among all that, the elaboration of a global model was not boarded that can help to choose the best alternative between the feasible ones, to elaborate the strategies and to evaluate the costs, and the authors propose to enter in that frame for study. As in all natural, technological and social changes, the best-prepared countries will have the best bear and the more rapid recover. In all the geographic areas the alternative will not be the same one, but the model must help us to make the appropriated decision. It is essential to know those areas that are more sensitive to the negative effects of climate change, the parameters to take into account for its evaluation, and comprehensive plans to deal with it. The objective of this paper is to elaborate a mathematical model support of decisions, which will allow to develop and to evaluate alternatives of adaptation to the climatic change of different communities in Europe and Latin-America, mainly in especially vulnerable areas to the climatic change, considering in them all the intervening factors. The models will consider criteria of physical type (meteorological, edaphic, water resources), of use of the ground (agriculturist, forest, mining, industrial, urban, tourist, cattle dealer), economic (income, costs, benefits, infrastructures), social (population), politician (implementation, legislation), educative (Educational programs, diffusion) and environmental, at the present moment and the future. The intention is to obtain tools for aiding to get a realistic position for these challenges, which are an important part of the future problems of humanity in next decades.
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σ32, the product of the rpoH gene in Escherichia coli, provides promoter specificity by interacting with core RNAP. Amino acid sequence alignment of σ32 with other sigma factors in the σ70 family has revealed regions of sequence homology. We have investigated the function of the most highly conserved region, 2.2, using purified products of various rpoH alleles. Core RNAP binding analysis by glycerol gradient sedimentation has revealed reduced core RNAP affinity for one of the mutant σ32 proteins, Q80R. This reduced core interaction is exacerbated in the presence of σ70, which competes with σ32 for binding of core RNAP. When a different but more conserved amino acid was introduced at this position by site-directed mutagenesis (Q80N), this mutant sigma factor still displayed a significant reduction in its core RNAP affinity. Based on these results, we conclude that at least one specific amino acid in region 2.2 is involved in core RNAP interaction.
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HLA-DR13 has been associated with resistance to two major infectious diseases of humans. To investigate the peptide binding specificity of two HLA-DR13 molecules and the effects of the Gly/Val dimorphism at position 86 of the HLA-DR beta chain on natural peptide ligands, these peptides were acid-eluted from immunoaffinity-purified HLA-DRB1*1301 and -DRB1*1302, molecules that differ only at this position. The eluted peptides were subjected to pool sequencing or individual peptide sequencing by tandem MS or Edman microsequencing. Sequences were obtained for 23 peptides from nine source proteins. Three pool sequences for each allele and the sequences of individual peptides were used to define binding motifs for each allele. Binding specificities varied only at the primary hydrophobic anchor residue, the differences being a preference for the aromatic amino acids Tyr and Phe in DRB1*1302 and a preference for Val in DRB1*1301. Synthetic analogues of the eluted peptides showed allele specificity in their binding to purified HLA-DR, and Ala-substituted peptides were used to identify the primary anchor residues for binding. The failure of some peptides eluted from DRB1*1302 (those that use aromatic amino acids as primary anchors) to bind to DRB1*1301 confirmed the different preferences for peptide anchor residues conferred by the Gly-->Val change at position 86. These data suggest a molecular basis for the differential associations of HLA-DRB1*1301 and DRB1*1302 with resistance to severe malaria and clearance of hepatitis B virus infection.
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This dissertation investigates China’s recent shift in its climate change policy with a refined discourse approach. Methodologically, by adopting a neo-Gramscian notion of hegemony, a generative definition of discourse and an ontological pluralist position, the study constructs a theoretical framework named “discursive hegemony” that identifies the “social forces” for enabling social change and focuses on the role of discursive mechanisms via which the forces operate and produce effects. The key empirical finding of this study was that it was a co-evolution of conditions that shaped the outcome as China’s climate policy shift. In examining the case, a before-after within-case comparison was designed to analyze the variations in the material, institutional, and ideational conditions, with methods including interviews, conventional narrative/text analysis and descriptive statistics. Specifically, changes in energy use, the structure of decision-making body, and the narratives about sustainable development reflected how the above three types of social force processed in China in the first few years of the 21st century, causing the economic development agenda to absorb the climate issue, and turning the policy frame for the latter from mainly a diplomatic matter to a potential opportunity for better-quality growth. With the discursive operation of the “Science-based development”, China’s energy policy has been a good example of the Chinese understanding of sustainability characterized by economic primacy, ecological viability and social green-engineering. This way of discursive evolution, however, is a double-edged sword that has pushed forward some fast, top-down mitigation measures on the one hand, but has also created and will likely continue creating social and ecological havoc on the other hand. The study makes two major contributions. First and on the empirical level, because China is an international actor that was not expected to cooperate on the climate issue according to major IR theories, this study would add one critical case to the studies on global (environmental) governance and the ideational approach in the IR discipline. Second and on the theory-building level, the model of discursive hegemony can be a causally deeper mode of explanation because it traces the process of co-evolution of social forces.
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Recent advances in statistical downscaling have allowed the reconstruction of temperatures for the complete 1948–2011 period in a spatial resolution of 90 m and without gaps for the Valencian Community (Spain) and bordering areas. It presently enables analyses in this region, which allows the determination of recent temperature changes at subregional and local scales. The present work focuses on obtaining the thermicity index according to Rivas-Martínez, a well-known indicator of different thermotypes associated with bioclimatic horizons. The change in this index, which has happened in the region between 1948 and 2011, was calculated by generating fine-scale maps of the potential extension of different thermotypes. The results show a greater regression for the thermotypes in a finicolous position, e.g. Orotemperate, Supratemperate and Supramediterranean horizons, which herein indicate greater potential vulnerability in climate change. In the absence of, and given the need for, such fine-scale information, this work should be useful for specialized researchers to spatially limit the potentially most vulnerable biotopes to climate change.
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In the five-year period 2005-09, Brazil has dramatically reduced carbon emissions by around 25% and at the same time has kept a stable economic growth rate of 3.5% annually. This combination of economic growth and emissions reduction is unique in the world. The driver was a dramatic reduction in deforestation in the Amazonian forest and the Cerrado Savannah. This shift empowered the sustainability social forces in Brazil to the point that the national Congress passed (December 2009) a very progressive law internalising carbon constraints and promoting the transition to a low-carbon economy. The transformation in Brazil’s carbon emissions profile and climate policy has increased the potentialities of convergence between the European Union and Brazil. The first part of this paper examines the assumption on which this paper is based, mainly that the trajectory of carbon emissions and climate/energy policies of the G20 powers is much more important than the United Nations multilateral negotiations for assessing the possibility of global transition to a low-carbon economy. The second part analyses Brazil’s position in the global carbon cycle and public policies since 2005, including the progressive shift in 2009 and the contradictory dynamic in 2010-12. The final part analyses the potential for a transition to a low-carbon economy in Brazil and the impact in global climate governance.
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The North Caucasus has been the most unstable region of the Russian Federation since the collapse of the Soviet Union. Considering the scale of violence, the conflict in the region should be regarded as a local civil war between the Salafi Islamic armed underground and the secular authorities of the North Caucasus republics, supported by the security services. The Chechen leader Ramzan Kadyrov, who has made himself de facto independent from Moscow, holds a particularly strong position in the region and his ambition is to gain control of the neighbouring territories. The Russian leadership, which sees the security of the Winter Olympics in Sochi as its top priority, is facing a strategic choice between trying to integrate the North Caucasus with the rest of the federation, or isolating the region and accepting the existence of an informal "internal abroad” within Russia. The cultural processes taking place in the region, including Islamisation, de-modernisation and de-Russification, have been driving the North Caucasus ever further away from the rest of Russia, strengthening a mutual sense of foreignness.
Resumo:
Russia was the first state in the world to de facto recognise the regime change in Kyrgyzstan that took place on 7 April 2010. This recognition, along with a previous campaign by the Russian media against the then President Kurmanbek Bakiyev, has given rise to suspicion that the events of April were provoked by Russia. However, it seems no more than reasonable to say that Russia provided some inspiration and lobbying in that direction. Russia offered support to the new Kyrgyz government almost immediately, albeit conditionally. Russia’s relations with Roza Otunbayeva’s government have been changing in nature; they are currently much cooler than they had been immediately after the coup. There are many indications that this change was a reaction to the extension of the lease agreement for the American military base in the Manas airport. At the same time, Moscow remains in contact with the political rivals to the current regime, which suggests that the Kremlin is preparing for different developments, and does not regard the current crisis as having been fully resolved. Despite the interim government’s plea for help, Russia refused to undertake military intervention in southern Kyrgyzstan, which plunged into ethnic unrest in June. This shows that Russia is wary of being dragged into a long-standing and bloody conflict in the region, which could entail considerable expenses and jeopardise Russia’s authority. It should be expected that after the October parliamentary elections in Kyrgyzstan, Russia will return to its plans to establish a second military base in this country (in addition to the Kant base) to reinforce its dominant position in the region. This is the first time that Russia has had a real chance to play a stabilising role in the CIS area. How Russia copes with this challenge may decide its position in post-Soviet Central Asia – and in a wider context, its relations with NATO, the USA and China.
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This study investigated how movement error is evaluated and used to change feedforward commands following a change in the environmental dynamics. In particular, we addressed the question of whether only position-error information is used or whether information about the force-field direction can also be used for rapid adaptation to changes in the environmental dynamics. Subjects learned to move in a position-dependent force field (PF) with a parabolic profile and the dynamics of a negative spring, which produced lateral force to the left of the target hand path. They adapted very rapidly, dramatically reducing lateral error after a single trial. Several times during training, the strength of the PF was unexpectedly doubled (PF2) for two trials. This again created a large leftward deviation, which was greatly reduced on the second PF2 trial, and an aftereffect when the force field subsequently returned to its original strength. The aftereffect was abolished if the second PF2 trial was replaced by an oppositely directed velocity-dependent force field (VF). During subsequent training in the VF, immediately after having adapted to the PF, subjects applied a force that assisted the force field for similar to 15 trials, indicating that they did not use information about the force-field direction. We concluded that the CNS uses only the position error for updating the internal model of the environmental dynamics and modifying feedforward commands. Although this strategy is not necessarily optimal, it may be the most reliable strategy for iterative improvement in performance.