Some message authentication codes (MACs) are vulnerable to multiple forgery attacks, in which an attacker can gain information that allows her to succeed in forging multiple message/tag pairs. This property was first noted in MACs based on universal hashing, such as the Galois/Counter Mode (GCM) of operation for block ciphers. However, we show that CBC-MAC and HMAC also have this property, and ...

A general circulation model (GCM) of intermediate complexity (Planet Simulator) is subjected to an analysis of the entropy budget and its sensitivity. The entropy production is computed directly based on temperature and temperature tendencies and estimated indirectly based on boundary fluxes. For indirect estimates, the model shows reasonably good agreement with observations. The direct computa...

A simple and feasible contact mode called gravitational contact mode (GCM) was developed for the first time to imitate the practical state between soot and catalyst. By simulating rainwater adsorption on a lawn in nature, we synthesized a lawn-like CuO nanorods array, which exhibited rather good catalytic activity for diesel soot combustion under GCM. Moreover, the CuO nanorods array could serv...

Abstract The density of the liquid Ti–V system was systematically measured using optical dilatometry method in electromagnetic levitation. Possible error sources have been discussed and minimized. A linear temperature dependency with negative slope found for all investigated alloys. Pure vanadium shows highest $${\rho }_{V}\left(T\right)=5.55\pm 0.03{\mathrm{gcm}}^{-3}-6.01\pm 0.52 {10}^{-4}{\m...

Introduction: The spectroscopic detection of methane in the atmosphere of Mars is the first observation of an organic compound on that planet [1-3]. CH4 has a lifetime of a few centuries, which suggests a young or current source. On the other hand, this lifetime is long enough for the atmospheric circulation to yield a uniform distribution of CH4 across the planet, which is not what is observed...

Neurons and glial cells differentiate from common precursors. Whereas the gene glial cells missing (gcm) determines the glial fate in Drosophila, current data about the expression patterns suggest that, in mammals, gcm homologues are unlikely to regulate gliogenesis. Here, we found that, in mouse retina, the bHLH gene Hes5 was specifically expressed by differentiating Müller glial cells and tha...

The authors propose a simple theory to explain a climatic drift previously found in a series of coupled general circulation model (GCM) experiments. Their theory places the GCM results on a simple stability diagram for the thermohaline circulation in the Atlantic. It is argued that the drift is due to Stommel’s salt advection feedback and arises because the particular spinup procedure of the co...

Multiple satellite records of tropical-mean water vapor are compared with a general circulation model (GCM) simulation to assess the ability to monitor and to predict low-frequency changes in total precipitable water. Particular attention is focused on the drying between 1979 and 1995 recorded by a TOVS statistical retrieval that is calibrated to radiosondes. Both a GCM integrated with observed...

R. Meyer, 2, ∗ Laurent J. Lewis, S. Prakash, and P. Entel Département de physique et Groupe de Recherche en Physique et Technologie des Couches Mince (GCM), Université de Montréal, C.P. 6128 Succursale Centre-ville, Montréal (Québec), Canada H3C 3J7 Institut für Physik, Universität Duisburg-Essen, Lotharstraße 1, D-47048 Duisburg, Germany Département de physique et Groupe de Recherche en Physiq...