Paleomagnetic reconstructions of sediments at ODP Sites 135-840 and 135-841

The geometry of the Tonga Arc implies that it has rotated approximately 17° clockwise away from the Lau Ridge as the Lau Basin formed in between. Questions have arisen about the timing of the opening, whether the arc behaved rigidly, and whether the opening occurred instead from motion of the Lau Ridge, the remanent arc. We undertook to address these questions by taking paleomagnetic samples from sediment cores drilled on the Tonga Arc at Sites 840 and 841, orienting the samples in azimuth, and comparing the paleodeclinations to expected directions. Advanced hydraulic piston corer (APC) cores from Holes 840C and 841A were oriented during drilling with a tool based on a magnetic compass and attached to the core barrel. Samples from Hole 841B were drilled with a rotary core barrel (RCB) and therefore are azimuthally unoriented. They were oriented by identifying faults and dipping beds in the core and aligning them with the same features in the Formation MicroScanner (FMS) wireline logs, which were themselves oriented with a three-axis magnetometer in the FMS tool. The best results came from the APC cores, which yielded a mean pole at -69.0°S, 112.2°E for an age of 4 Ma. This pole implies a declination anomaly of 20.8° ± 12.6° (95% confidence limit), which appears to have occurred by tectonic rotation of the Tonga Arc. This value is almost exactly that expected from the geometry of the arc and implies that it did indeed rotate clockwise as a rigid body. The large uncertainty in azimuth results from core orientation errors, which have an average standard deviation of 18.6°. The youngest cores used to calculate the APC pole contain sediments deposited during Subchron 2A (2.48-3.40 Ma), and their declinations are indistinguishable from the others. This observation suggests that most of the rotation occurred after their deposition; this conclusion must be treated with caution, however, because of the large azimuthal orientation errors. Poles from late and early Miocene sediments of Hole 841B are more difficult to interpret. Samples from this hole are mostly normal in polarity, fail a reversal test, and yield poles that suggest that the normal-polarity directions may be a recent overprint. Late Miocene reversed-polarity samples may be unaffected by this overprint; if so, they imply a declination anomaly of 51.1° ± 11.5°. This observation may indicate that, for older sediments, Tonga forearc rotations are larger than expected.

From foot-draggers to strategic counter-partners : the dynamics of U.S. and Chinese policies for tackling climate change

As can been seen from the U.S.'s non-ratification of the Kyoto Protocol, together with the negotiations toward the post-Kyoto Protocol framework, the U.S. and China have been quarrelling over their responsibilities and have contradicted one another over the introduction of compulsory domestic greenhouse gases emission reduction targets. Therefore, for a long time, it has been argued that the controversy between the two countries has hindered the process of forging an international agreement to deal with climate change. On the other hand, Sino-U.S. bilateral cooperation on climate change has significantly increased in recent years in summit talks and their Strategic & Economic Dialogue (S&ED), especially after the 15th Conference of Parties (COP) of the United Nations Framework Convention on Climate Change (UNFCCC) in Copenhagen, one of whose aims was to facilitate positive negotiations for the post-Kyoto Protocol agreement. Analyzing this in the light of recent developments, we find that the U.S. and China have tended to address climate change and related issues from a pluralistic viewpoint and approach, by regarding the achievement of bilateral cooperation and global agreements as their common strategic objective.

A visual object counter based on a multimodal data association for embedded systems with limited computational power

A low complex but highly-efficient object counter algorithm is presented that can be embedded in hardware with a low computational power. This is achieved by a novel soft-data association strategy that can handle multimodal distributions.

Counter bond, 1724/5 January 22

Handwritten counter bond between Samuel Whittemore and Andrew Bordman, securing Whittemore's loan from Nathaniel Hancock and James Reade.

Counter bond, 1728 June 5

Handwritten counter bond between Francis Foxcroft and Jonathan Remington, securing Foxcroft's loan from Andrew Bordman.

Counter bond, 1731 August 4

Handwritten counter bond between Stephen Palmer and Samuel Whittemore, and Edward Hutchinson, securing Stephen Palmer and Samuel Whittemore's loan from William Brattle and Andrew Bordman.

Narratives and counter-narratives on "marriage of convenience" : conjugality and (il)legality in portuguese migration policies and in couples’ experiences

Tese de doutoramento, Sociologia (Sociologia da Família, Juventude e das Relações do Género), Universidade de Lisboa, Instituto de Ciências Sociais, 2016

Counter-reforms in times of prosperity. OSW Point of View, September 2006

In 2000, Vladimir Putin came to power after nearly a decade of the rule of the first Russian president, Boris Yeltsin. As prime minister, and later as a candidate for president, Putin announced that he would reform the state. The main assumptions of this reform were presented during a congress of the pro-Kremlin Unity movement, in Putin's address entitled 'Russia at the turn of the millennium' which was delivered on 29 December 1999, and later in a open letter to voters published on 25 February 2000. Both declarations were rather general, but they gave a clear picture of the principal directions of and priority areas for the future president's efforts: they outlined Russia's development path as pro-market and democratic. Nearly seven years have passed since Vladimir Putin came to power, a time for a summary of his achievements. In a way, Vladimir Putin has partially delivered on his initial declarations; indeed, Russia has undergone a deep transformation. However, when seen in the light of the president’s initial promises, the changes appear to be no more than 'counter-reforms', because instead of putting into practice the policy he outlined seven years ago, they have largely followed a different, if not entirely opposite direction.