Cuckoldry features of introduced pumpkinseed sunfish (Lepomis gibbosus) in contrasting environmental conditions in southern Europe

Reproduction of pumpkinseed sunfish ( Lepomis gibbosus (L., 1758)) in the species’ native range often involves cuckoldry, consisting of dominant nest-guarding (parental) males and the participation by small “sneaker” males. However, it remains unknown whether this behaviour occurs in populations of non-native pumpkinseed. Thus, the present study describes the phenotypic features of cuckoldry under contrasting environmental conditions (lentic versus lotic) in southern Europe. Parental and sneaker pumpkinseeds were captured in the summer of 2011 from the River Bullaque (central Spain) and from the Encinarejo Reservoir (southern Spain). No differences in total length were observed in sneaker males, although individuals of ages 1+ and 2+ were significantly predominant in the river and the reservoir, respectively. Parental males were larger and older in the reservoir than in the river. Gonadosomatic and hepatosomatic indices were significantly higher in sneaker than in parental males at both sites. Body condition was lower in sneaker males in the river. Both ingested biomass and the proportion of full stomachs were lower in parental males at both sites, being significant in all cases except ingested biomass in the river. Sneaker males achieved a higher gonadosomatic index than parental males. In contrast, parental males had higher body condition indices than sneakers. Results demonstrate the high ecological plasticity of pumpkinseed sunfish to display natural behaviours out of its native area.

Communication gaps in knowledge of freshwater fish biodiversity: implications for the management and conservation of Mexican biosphere reserves

To detect differences in the information available on freshwater fish species found in Mexican biosphere reserves, the number of species considered in three sources of information: management programmes, Global Biodiversity Information Facility (GBIF) and the scientific literature were compared. Additionally, management actions for the reserves were evaluated. More than 55% of freshwater fish species registered for the reserves were found only in one of the three sources of information, while just 12% was shared among all the three. Fifteen threatened species were registered in GBIF and the scientific literature that were not found in management programmes. Although all the management programmes described conservation actions, none of them gave details about how they would be implemented. Lack of communication among the sources studied, unawareness of the existence of threatened species and the absence of detailed management actions hinder the development of adequate conservation strategies.

Artificial intelligence techniques: predicting necessity for biopsy in renal transplant recipients suspected of acute cellular rejection or nephrotoxicity

The gold standard for nephrotoxicity and acute cellular rejection (ACR) is a biopsy, an invasive and expensive procedure. More efficient strategies to screen patients for biopsy are important from the clinical and financial points of view. The aim of this study was to evaluate various artificial intelligence techniques to screen for the need for a biopsy among patients suspected of nephrotoxicity or ACR during the first year after renal transplantation. We used classifiers like artificial neural networks (ANN), support vector machines (SVM), and Bayesian inference (BI) to indicate if the clinical course of the event suggestive of the need for a biopsy. Each classifier was evaluated by values of sensitivity and area under the ROC curve (AUC) for each of the classifiers. The technique that showed the best sensitivity value as an indicator for biopsy was SVM with an AUC of 0.79 and an accuracy rate of 79.86%. The results were better than those described in previous works. The accuracy for an indication of biopsy screening was efficient enough to become useful in clinical practice.

Role of dispersion forces in the structure of graphene monolayers on Ru surfaces

Elaborate density functional theory (DFT) calculations that include the effect of van der Waals (vdW) interactions have been carried out for graphene epitaxially grown on Ru(0001). The calculations predict a reduction of structural corrugation in the observed moiré pattern of about 25% (∼0.4 Å) with respect to DFT calculations without vdW corrections. The simulated STM topographies are close to the experimental ones in a wide range of bias voltage around the Fermi level.

Built-in mechanical stress in viral shells

Mechanical properties of biological molecular aggregates are essential to their function. A remarkable example are double-stranded DNA viruses such as the φ29 bacteriophage, that not only has to withstand pressures of tens of atmospheres exerted by the confined DNA, but also uses this stored elastic energy during DNA translocation into the host. Here we show that empty prolated φ29 bacteriophage proheads exhibit an intriguing anisotropic stiffness which behaves counterintuitively different from standard continuum elasticity predictions. By using atomic force microscopy, we find that the φ29 shells are approximately two-times stiffer along the short than along the long axis. This result can be attributed to the existence of a residual stress, a hypothesis that we confirm by coarse-grained simulations. This built-in stress of the virus prohead could be a strategy to provide extra mechanical strength to withstand the DNA compaction during and after packing and a variety of extracellular conditions, such as osmotic shocks or dehydration.

Potential energy landscape for hot electrons in periodically nanostructured graphene

We explore the spatial variations of the unoccupied electronic states of graphene epitaxially grown on Ru(0001) and observed three unexpected features: the first graphene image state is split in energy; unlike all other image states, the split state does not follow the local work function modulation, and a new interfacial state at +3  eV appears on some areas of the surface. First-principles calculations explain the observations and permit us to conclude that the system behaves as a self-organized periodic array of quantum dots.

Reactivity of periodically rippled graphene grown on Ru(0001)

We report here the reactivity of epitaxial graphene islands and complete monolayers on Ru(0001) towards molecular oxygen and air. The graphene is prepared by thermal decomposition of ethylene molecules pre-adsorbed on an Ru(0001) surface in an ultra-high vacuum chamber. The graphene layer presents a periodically rippled structure that is dictated by the misfit between graphene and Ru(0001) lattice parameters. The periodic ripples produce spatial charge redistribution in the graphene and modifies its electronic structure around the Fermi level. In order to investigate the reactivity of graphene we expose graphene islands to a partial pressure of oxygen and following the evolution of the surface by STM during the exposure. For the exposure to air we removed the sample from the UHV chamber and we re-introduce it after several hours, taking STM images before and after. The surface areas not covered by the graphene islands present a dramatic change but the graphene structure, even the borders of the islands, remain intact. In the case of a complete graphene monolayer the exposure to oxygen or to air does not affect or destroy the rippled structure of the graphene monolayer.