Space-irrelevant scaling law for fish school sizes

Universal scaling in the power-law size distribution of pelagic fish schools is established. The power-law exponent of size distributions is extracted through the data collapse. The distribution depends on the school size only through the ratio of the size to the expected size of the schools an arbitrary individual engages in. This expected size is linear in the ratio of the spatial population density of fish to the breakup rate of school. By means of extensive numerical simulations, it is verified that the law is completely independent of the dimension of the space in which the fish move. Besides the scaling analysis on school size distributions, the integrity of schools over extended periods of time is discussed.Comment: 23 pages, 12 figures, to appear in J. Theor. Bio

The ATLAS trigger - high-level trigger commissioning and operation during early data taking

The ATLAS experiment is one of the two general-purpose experiments due to start operation soon at the Large Hadron Collider (LHC). The LHC will collide protons at a centre of mass energy of 14~TeV, with a bunch-crossing rate of 40~MHz. The ATLAS three-level trigger will reduce this input rate to match the foreseen offline storage capability of 100-200~Hz. This paper gives an overview of the ATLAS High Level Trigger focusing on the system design and its innovative features. We then present the ATLAS trigger strategy for the initial phase of LHC exploitation. Finally, we report on the valuable experience acquired through in-situ commissioning of the system where simulated events were used to exercise the trigger chain. In particular we show critical quantities such as event processing times, measured in a large-scale HLT farm using a complex trigger menu

The Association of Cardio-Ankle Vascular Index and Ankle-Brachial Index with Macroangiopathy in Patients with Type 2 Diabetes Mellitus

Aims: This study elucidates the association of macroangiopathy development in type 2 diabetes patients with various arteriosclerosis risk factors (ARFs) and results of cardio-ankle vascular index (CAVI) and ankle-brachial pressure index (ABI).Methods: The correlation between current and past macroangiopathy development, with ARFs or CAVI/ABI data, was retrospectively analyzed using multivariate logistic regression in 816 patients with type 2 diabetes at a single center. C-statistics combining some independent variables selected using the stepwise method were evaluated.Results: CAVI was significantly correlated with microangiopathies, including coronary artery disease (CAD), arteriosclerosis obliterans (ASO), and stroke with odds ratios (OR) of 1.20, 1.22, and 1.19, respectively. ABI significantly correlated with ASO and stroke with respective OR of 13.6 and 2.47, but not with CAD. Areas under the receiver operating characteristic curves (ROCs) revealed the accuracy of detecting ASO and stroke was increased by the combination of CAVI＋ABI (0.94 and 0.74, respectively). However, areas under the ROC for the presence of CAD can be increased by the combination of CAVI and ARFs especially including dyslipidemia.Conclusion: CAVI/ABI and some ARFs are useful tools in daily clinical care units to identify the current and past existence of macroangiopathy in patients with type 2 diabetes, but the prediction weights using these factors were different among CAD, ASO, and stroke

A simultaneous multiwavelength dispersive X-ray reflectometer for time-resolved reflectometry

Aiming for the realization of time-resolved specular X-ray reflectivity measurements on the sub-second to millisecond timescales, a conceptually new method of measuring specular X-ray reflectivity curves is developed. Using this method the entire profile of the reflectivity curve of interest is measured in place. A horizontally convergent X-ray beam which has a one-to-one correlation between its direction and energy is realized using a curved crystal or laterally graded multilayers on an elliptic substrate. The X-ray beam is then incident on the surface of the specimen placed at the focus such that the glancing angle in the vertical direction is the same for all X-ray components, which are reflected in the vertical direction by the surface and diverge in the horizontal plane. The perpendicular momentum transfer continuously changes as a function of the horizontal ray direction even with fixed glancing angle since the wavelength (energy) changes. The X-ray intensity distribution across the beam direction measured downstream of the specimen using a one- or two-dimensional detector represents the X-ray reflectivity curve. Specular X-ray reflectivity curves are measured with exposure times ranging from 2 ms to 1 s for a gold film of thickness 14.3 nm on a silicon substrate. The potential of this method for time-resolved measurements is demonstrated by recording reflectivity curves with a time resolution of 20 ms from a rotating specimen