Dynamical hierarchy in transition states: Why and how does a system climb over the mountain?

How a reacting system climbs through a transition state during the course of a reaction has been an intriguing subject for decades. Here we present and quantify a technique to identify and characterize local invariances about the transition state of an N-particle Hamiltonian system, using Lie canonical perturbation theory combined with microcanonical molecular dynamics simulation. We show that at least three distinct energy regimes of dynamical behavior occur in the region of the transition state, distinguished by the extent of their local dynamical invariance and regularity. Isomerization of a six-atom Lennard–Jones cluster illustrates this: up to energies high enough to make the system manifestly chaotic, approximate invariants of motion associated with a reaction coordinate in phase space imply a many-body dividing hypersurface in phase space that is free of recrossings even in a sea of chaos. The method makes it possible to visualize the stable and unstable invariant manifolds leading to and from the transition state, i.e., the reaction path in phase space, and how this regularity turns to chaos with increasing total energy of the system. This, in turn, illuminates a new type of phase space bottleneck in the region of a transition state that emerges as the total energy and mode coupling increase, which keeps a reacting system increasingly trapped in that region.

The effect of electricity tariffs over the operating costs of the Spanish wastewater treatments plants

Given the complex structure of electricity tariffs and their steady growth in Spanish, we've studied its effect over the operating costs of the wastewater treatment plants (WWTP), concluding that in the last three years the revisions of electricity rates have meant increases in electricity costs of 64.5% in the rate 3.1.A and 79.1% in the rate 6.1. This has caused the cost of electricity, which was the most important, has increased from a 44% of total operating costs in the year 2009, to more than a 56% in the year 2012.

SCAPHOID AND LUNATE CARPAL MECHANICS OVER THE SPECTRUM OF HEALTHY FUNCTION

When ligaments within the wrist are damaged, the resulting loss in range of motion and grip strength can lead to reduced earning potential and restricted ability to perform important activities of daily living. Left untreated, ligament injuries ultimately lead to arthritis and chronic pain. Surgical repair can mitigate these issues but current procedures are often non-anatomic and unable to completely restore the wrist’s complex network of ligaments. An inability to quantitatively assess wrist function clinically, both before and after surgery, limits the ability to assess the response to clinical intervention. Previous work has shown that bones within the wrist move in a similar pattern across people, but these patterns remain challenging to predict and model. In an effort to quantify and further develop the understanding of normal carpal mechanics, we performed two studies using 3D in vivo carpal bone motion analysis techniques. For the first study, we measured wrist laxity and performed CT scans of the wrist to evaluate 3D carpal bone positions. We found that through mid-range radial-ulnar deviation range of motion the scaphoid and lunate primarily flexed and extended; however, there was a significant relationship between wrist laxity and row-column behaviour. We also found that there was a significant relationship between scaphoid flexion and active radial deviation range of motion. For the second study, an analysis was performed on a publicly available database. We evaluated scapholunate relative motion over a full range of wrist positions, and found that there was a significant amount of variation in the location and orientation of the rotation axis between the two bones. Together the findings from the two studies illustrate the complexity and subject specificity of normal carpal mechanics, and should provide insights that can guide the development of anatomical wrist ligament repair surgeries that restore normal function.

Bilateral Disputes – A dark cloud over the Balkans. CEPS Commentary, 24 January 2014

Countless bilateral disputes continue to plague the Balkan region; daily reminders of the region's troubled history. Not only are they the cause of tension between the countries of the region both inside and outside the EU, they also undermine efforts to integrate the region into the EU. To avoid the risk of instability and further erosion of the credibility of the EU's enlargement strategy, urgent action is required. The author sets out four recommendations for the EU to pursue without delay.

The OTC derivatives markets after financial reforms. CEPS ECMI Commentary No. 36, May 2014

Over the past five years, over-the-counter (OTC) derivatives markets have received heightened regulatory attention, due to their opaqueness, size and interconnectedness, with a view to improving the robustness, safety and resilience of this market segment. There has been continued progress in the follow-up to the G-20 commitments, with the EU (EMIR, MIFID II, CRD/CRR IV, MAD) and the US (Swap Execution Facility or SEF, Title VII of Dodd-Frank Act, Basel III) leading in the implementation timelines and capturing approximately 80-90% of the overall market. Based on the data compiled for the yearly ECMI Statistical Package, this commentary provides a snapshot of the current status of the global OTC derivatives markets by: i) identifying general trends over the past decade, ii) looking at the changes in the market structure (instruments and participants), iii) estimating the uncollateralised derivatives exposure and iv) examining the relationship between OTC derivatives and exchange-traded derivatives (ETD).