The V4 region of the small subunit (18S) ribosomal RNA was examined in 72 different sequences representing a broad sample eukaryotic diversity. This domain is the most variable region of the 18S rRNA molecule and ranges in length from ca. 230 to over 500 bases. Based upon comparative analysis, secondary structural models were constructed for all sequences and the resulting generalized model sho...

Among secondary structure elements, beta-turns are ubiquitous and major feature of bioactive peptides. We analyzed 77 biologically active peptides with length varying from 9 to 20 residues. Out of 77 peptides, 58 peptides were found to contain at least one beta-turn. Further, at the residue level, 34.9% of total peptide residues were found to be in beta-turns, higher than the number of helical ...

The deposition of X-ray data along with the customary structural models defining PDB entries makes it possible to apply large-scale re-refinement protocols to these entries, thus giving users the benefit of improvements in X-ray methods that have occurred since the structure was deposited. Automated gradient refinement is an effective method to achieve this goal, but real-space intervention is ...

Brittle deformation can saturate the Earth's crust with faults and fractures in an apparently chaotic fashion. The details of brittle deformational histories and implications on, for example, seismotectonics and landscape, can thus be difficult to untangle. Fortunately, brittle faults archive subtle details of the stress and physical/chemical conditions at the time of initial strain localizatio...

In this work, we develop a fully automated method for the quality assessment prediction of protein structural models generated by structure prediction approaches such as fold recognition servers, or ab initio methods. The approach is based on fragment comparisons and a consensus C(alpha) contact potential derived from the set of models to be assessed and was tested on CASP7 server models. The a...

The type VI secretion system (T6SS) is a complex and widespread gram-negative bacterial export pathway with the capacity to translocate protein effectors into a diversity of target cell types. Current structural models of the T6SS indicate that the apparatus is composed of at least two complexes, a dynamic bacteriophage-like structure and a cell-envelope-spanning membrane-associated assembly. H...

nonlinear analyses allow simulating, in a more realistic way, the behaviour of structuressubjected to several types of complex loading conditions such as earthquakes. however, it isrecognized that these analyses normally generate a considerable amount of results, a factorthat difficult its interpretation. over the last years, considerable progresses have been made instructural nonlinear behavio...

corrosion of steel reinforcement is one of the most prevalent causes of reinforced concrete (rc) structures deterioration in chloride-contaminated environments. as a result, evaluating the impact of any possible corrosion-induced damages to reinforced concrete bridges strongly affects management decisions: such as inspection, maintenance and repair actions. the corrosion propagation phase is a ...

Two competing structural models were tested in an effort to develop a theory of learned hopefulness. Learned hopefulness suggests that empowering experiences-ones that provide opportunities to learn skills and develop a sense of control-can help individuals limit the debilitating effects of problems in living. Voluntary organizations are identified as natural settings that enable individuals to...

The authors provide a comprehensive and useful review of structural models in marketing (Chintagunta et al. 2006). They evaluate the strengths and limitations of a structural approach and present examples of recent advancements in the development and application of structural models. Their discussion on the directions for future studies is very insightful. Despite the growing trend in the liter...