The main objective of this paper is to solve the problem of finding graphs on which the spectral clustering method and the normalized cut produce different partitions. To this end, we derive formulae for minimum normalized cut for graphs in some classes such as paths, cycles, complete graphs, double-trees, lollipop graphs LPn,m, roach type graphs Rn,k and weighted paths Pn,k.

Abstract Greater Prespa Lake, located on the Balkan Peninsula, is an ancient freshwater lake inhabited by numerous endemic and endangered species represents important part of Europe’s natural heritage. Between 2013 2015, standardized gillnet fishing was conducted for first time ever with aim obtaining large-scale information status fish community in terms relative abundance, biomass, spatial di...

Acute mountain sickness Many hundreds of studies of AMS over the past two centuries have examined the contributions of ventilation, pulmonary gas exchange and fluid balance to the pathophysiology of AMS. Unfortunately, the traditional paradigm that invoked these peripheral responses to acute hypobaric hypoxia to explain AMS failed to substantially advance our understanding. Therefore, this revi...

Glycogen, a branched polymer of glucose, forms an energy re-serve in numerous organisms. In mammals, the two largest glyco-gen stores are in skeletal muscle and liver, which express tissue-specific glycogen synthase isoforms. MGSKO mice, in which mGys1 (mouse glycogen synthase) is disrupted, are devoid of muscle glycogen [Pederson, Chen, Schroeder, Shou, DePaoli-Roach and Roach (2004) Mol. Cell...

We examined the diversity of a marker gene for homoacetogens in two cockroach gut microbial communities. Formyltetrahydrofolate synthetase (FTHFS or fhs) libraries prepared from a wood-feeding cockroach, Cryptocercus punctulatus, were dominated by sequences that affiliated with termite gut treponemes. No spirochete-like sequences were recovered from the omnivorous roach Periplaneta americana, w...

The ecological features of invasive alien species are crucial for their effective management. However, they often lacking in newly invaded ecosystems. This is the case European catfish Silurus glanis L. Lake Maggiore, where present since 1990, but no scientific information available on its ecology. To start filling this knowledge gap, 236 (67 cm to 150 total length) were collected, measured, an...

Quantifying the effects of human activity on the natural environment is dependent on credible estimates of reference conditions to define the state of the environment before the onset of adverse human impacts. In Europe, emission controls that aimed at restoring ecological status were based on hindcasts from process-based models or paleolimnological reconstructions. For instance, 1860 is used i...

Generalist species commonly have a fundamental role in ecosystems as they can integrate spatially distinct habitats and food-web compartments, as well as control the composition, abundance and behavior of organisms at different trophic levels. Generalist populations typically consist of specialized individuals, but the potential for and hence degree of individual niche variation can be largely ...

Submerged macrophytes are essential elements of sublittoral ecosystems to maintain a diverse fish fauna. The aim this study was assess juvenile associated with macrophyte habitats in the Curonian Lagoon by means modified pop net method. We focused on two dominant littoral different structure (pondweed and charophyte stands). nets sampling carried out sites located freshwater oligohaline part la...