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Laplace operators on metric graphs are considered. It is proven that for compact graphs the spectrum of the Laplace operator determines the total length, the number of connected components, and the Euler characteristic. For a class of non-compact graphs the same characteristics are determined by the scattering data consisting of the scattering matrix and the discrete eigenvalues.

Two systems for measurements of absorption and scattering properties, based on picosecond-pulse lasers and single-photon counting detection, were characterized using a detailed protocol. The first system utilizes diode lasers at 660, 785, 910 and 974 nm as light sources. The second employs a Ti:sapphire and a mode-locked dye laser to produce tunable pulses in the range 610 - 1000 nm. Using solid t

This paper expands Ghaddar et al. [N. Ghaddar, K. Ghali, R. Saadeh, A. Keblawi, Design charts for combined chilled ceiling displacement ventilation system (1438-RP), ASHRAE Transactions, 143 (2) (2008) 574-587] design charts of combined chilled ceiling (CC) displacement ventilation (DV) system to operating sensible load ranges from 40 W/m(2) to 100 W/m(2). It develops a global correlation of syste

This study investigates factors of importance for tadpoles survival and metamorph production in the common frog Rana temporaria. It also assess the importance of this for the population dynamics of the species. Eighteen ponds were studied for up to 8 years. Data collected each year included: number of spawn clumps deposited, tadpole number and metamorph number. The permanency of the ponds was also

AIMS: Red cell distribution width (RDW) has been associated with cardiovascular disease, but the relation to heart failure (HF) is unclear. We investigated the association between RDW and incidence of first hospitalization due to HF in a population-based cohort. METHODS AND RESULTS: Red cell distribution width was measured in 26 784 subjects (aged 45-73 years, 61% women), without history of myocar

Purpose: To assess the associations of meniscal tears, knee malalignment, cartilage damage, knee effusion, and body mass index with meniscal extrusion. Materials and Methods: The Multicenter Osteoarthritis study is an observational study of individuals who have or are at risk for knee osteoarthritis (OA). The HIPAA-compliant protocol was approved by the institutional review boards of all particip

We prove the existence of steady periodic capillary water waves on flows with arbitrary vorticity distributions. They are symmetric two-dimensional waves whose profiles are monotone between crest and trough.

Fuel Taxes and the Poor challenges the conventional wisdom that gasoline taxation, an important and much-debated instrument of climate policy, has a disproportionately detrimental effect on poor people. Increased fuel taxes carry the potential to mitigate carbon emissions, reduce congestion, and improve local urban environment. As such, higher gasoline taxes could prove to be a fundamental part of