A simple model for solid friction is analyzed. It is based on tangential springs representing interlocked asperities of the surfaces in contact. Each spring is given a maximal strain according to a probability distribution. At their maximal strain the springs break irreversibly. Initially all springs are assumed to have zero strain, because at static contact local elastic stresses are expected ...

The production of hydrogen and methane by geochemical reactions associated with the serpentinization of ultramafic rocks can potentially support subsurface microbial ecosystems independent of the photosynthetic biosphere. Methanogenic and methanotrophic microorganisms are abundant in marine hydrothermal systems heavily influenced by serpentinization, but evidence for methane-cycling archaea and...

Contradictions between system-specific evidence and broader paradigms to explain ecosystem behavior present a challenge for natural resource management. In Florida (U.S.A.) springs, increasing nitrate (NO3-) concentrations have been implicated as the cause of algal overgrowth via alleviation of N-limitation. As such, policy and management efforts have centered heavily on reduction of nitrogen (...

The carbon isotope content of dissolved inorganic carbon was measured for large cold springs in the central Oregon Cascades. Low 14C activities in some of the springs are interpreted to result from the dissolution of diffuse emissions of magmatic CO2, even though volcanic activity has not occurred in this area for more than 1300 yr. On the basis of dissolved magmatic carbon concentrations in th...

We know of some 650 holy springs in Denmark. Their abundance seems to be the reason why a decade ago one of Denmark's leading authorities on late-medieval archaeology wrote that the popular worship of saints in that country appeared to be more closely connected to the cult of holy springs than anywhere else in Europe.' This statement was apparently based largely on post-Reformation sources. A v...

_______________ This study investigated the performance of native and non native speakers of Modern Greek language on morphology and syntax tasks. Non-native speakers of Greek whose native language was English, which is a language with strict word order and simple morphology, made more errors and answered more slowly than native speakers on morphology but not syntax tasks. It seems that Greek f...

The term nanotechnology was first used in 1974 by the late Norio Taniguchi (University of Tokyo) to refer to the ability to engineer materials precisely at the scale of nanometres. This is in fact its current meaning; ‘engineer materials’ is usually taken to comprise the design, characterization, production and application of materials, and the scope has nowadays been widened to include devices...

How does cross-linguistic variation in linguistic structure affect children's acquisition of early number word meanings? We tested this question by investigating number word learning in two unrelated languages that feature a tripartite singular-dual-plural distinction: Slovenian and Saudi Arabic. We found that learning dual morphology affects children's acquisition of the number word two in bot...

This paper investigates the semantics of kind-referring expressions and of generic quantification in Brazilian Portuguese (BP). It may thus be taken as a contribution to the development of a more accurate understanding of genericity as a crosslinguistic phenomenon. In BP genericity may be expressed by both definite singular (1) and definite plural (2) nominals, and also by indefinite nominals s...

The correct use of an affix, such as the English plural suffix, may reflect mastery of a morphological process but it may also depend on children's syntactic, semantic and phonological abilities. The present paper reports a set of experiments in support of this latter view, specifically focusing on the importance of the phonological make-up of plural forms for both production and comprehension....