Empirical corrections and pair interaction energies in the fragment molecular orbital method

The energy and analytic gradient are developed for FMO combined with the Hartree-Fock method augmented with three empirical corrections (HF-3c). The auxiliary basis set approach to FMO is extended to perform pair interaction energy decomposition analysis. The FMO accuracy is evaluated for several typical systems including 3 proteins. Pair interaction energies computed with different approaches in FMO are compared for a water cluster and protein-ligand complexes.Comment: Revised version accepted in Chemical Physics Letter

Weak randomness completely trounces the security of QKD

In usual security proofs of quantum protocols the adversary (Eve) is expected to have full control over any quantum communication between any communicating parties (Alice and Bob). Eve is also expected to have full access to an authenticated classical channel between Alice and Bob. Unconditional security against any attack by Eve can be proved even in the realistic setting of device and channel imperfection. In this Letter we show that the security of QKD protocols is ruined if one allows Eve to possess a very limited access to the random sources used by Alice. Such knowledge should always be expected in realistic experimental conditions via different side channels

Threshold concepts and metalearning capacity

This study operationalises the empowering concept of metalearning in the specific context of engagement with a threshold concept. An experience of metalearning was constituted in two parts. First students' awareness of themselves as learners is prompted by, and focuses on, a learning profile that is generated online through the completion of the Reflections on Learning Inventory (RoLI). Second, students are given an opportunity to interpret their respective profiles and write a short and undirected reflective account of their interpretation. The second part of the experience focuses not only on students' awareness but also on their capacity to control their future learning on the basis of their heightened awareness.

Dynamics of conduction blocks in a model of paced cardiac tissue

We study numerically the dynamics of conduction blocks using a detailed electrophysiological model. We find that this dynamics depends critically on the size of the paced region. Small pacing regions lead to stationary conduction blocks while larger pacing regions can lead to conduction blocks that travel periodically towards the pacing region. We show that this size-dependence dynamics can lead to a novel arrhythmogenic mechanism. Furthermore, we show that the essential phenomena can be captured in a much simpler coupled-map model.Comment: 8 pages 6 figure

New Facts About Factor-Demand Dynamics: Employment, Jobs, and Workers

We provide a unified discussion of the relations among flows of workers, changes in employment and changes in the number of jobs at the level of the firm. Using the only available set of data (a nationally representative sample of Dutch firms in 1988 and 1990) we discover that: 1) Nearly half of all hiring is by firms where employment is not growing; 2) Over half of all firing is by firms that are not contracting; 3) Most firing is by firms that are also hiring; 4) Flows of workers within firms are small compared to flows into and out of firms; and 5) Accounting for simultaneous creation and destruction of jobs within firms adds roughly 15 percent to estimates of economywide job creation and destruction. The results imply that macroeconomic fluctuations can have substantial effects beyond those indicated by net employment changes at the firm level, and that studies of dynamic factor demand must account for variations in gross flows of workers.

Interface of the polarizable continuum model of solvation with semi-empirical methods in the GAMESS program

An interface between semi-empirical methods and the polarized continuum model (PCM) of solvation successfully implemented into GAMESS following the approach by Chudinov et al (Chem. Phys. 1992, 160, 41). The interface includes energy gradients and is parallelized. For large molecules such as ubiquitin a reasonable speedup (up to a factor of six) is observed for up to 16 cores. The SCF convergence is greatly improved by PCM for proteins compared to the gas phase

A Study of Anyon Statistics by Breit Hamiltonian Formalism

We study the anyon statistics of a $2 + 1$ dimensional Maxwell-Chern-Simons (MCS) gauge theory by using a systemmetic metheod, the Breit Hamiltonian formalism.Comment: 25 pages, LATE