Analytical Solutions of Viscoelastic Nonlocal Timoshenko Beams

A consistent nonlocal viscoelastic beam model is proposed in this paper. Specifically, a Timoshenko bending problem, where size-and time-dependent effects cannot be neglected, is investigated. In order to inspect scale phenomena, a stress-driven nonlocal formulation is used, whereas to simulate time-dependent effects, fractional linear viscoelasticity is considered. These two approaches are adopted to develop a new Timoshenko bending model. Analytical solutions and application samples of the proposed formulation are presented. Moreover, in order to show influences of viscoelastic and size effects on mechanical response, parametric analyses are provided. The contributed results can be useful for the design and optimization of small-scale devices exhibiting flexural behaviour

Hierarchical Spatial Organization of Geographical Networks

In this work we propose the use of a hirarchical extension of the polygonality index as a means to characterize and model geographical networks: each node is associated with the spatial position of the nodes, while the edges of the network are defined by progressive connectivity adjacencies. Through the analysis of such networks, while relating its topological and geometrical properties, it is possible to obtain important indications about the development dynamics of the networks under analysis. The potential of the methodology is illustrated with respect to synthetic geographical networks.Comment: 3 page, 3 figures. A wokring manuscript: suggestions welcome

Data managers: A survey of the European Society of Breast Cancer Specialists in certified multi-disciplinary breast centers.

The European Society of Breast Cancer Specialists (EUSOMA) requires that the breast centers' core team includes a trained person responsible for data collection and analysis. We addressed a questionnaire to the data managers of the EUSOMA breast centers network in order to acquire information with regard to their education, training, role, activity, recognition, and satisfaction. Breast centers' data managers are highly educated individuals with a variety of backgrounds carrying out, more frequently part-time and as temporary employees, a job for which they received little specific training. These findings support the importance of defining a core curriculum and a training program

Agronomic, nutritional and nutraceutical aspects of durum wheat (Triticum durum Desf.) cultivars under low input agricultural management

Among cereals, durum wheat has a central role in the Italian diet and economy, where there is a historical tradition of pasta making. In the present study, we evaluated the nutrient and nutraceutical properties of 2 old and 6 modern durum wheat varieties grown under low input agricultural management. Considering the lack of available data on the adaptability of existing durum wheat varieties to the low input and organic sectors, the research aimed at providing a complete description of the investigated genotypes, considering the agronomic performance as well as the nutrient and phytochemical composition. The experimental trials were carried out at the same location (Bologna, Northern Italy) for two consecutive growing seasons (2006/2007, 2007/2008). No clear distinction between old and modern varieties was observed in terms of grain yield (mean values ranging from 2.5 to 4.0 t/ha), highlighting that the divergence in productivity, normally found between dwarf and non-dwarf genotypes, is strongly reduced when they are cropped under low input management. All durum wheat varieties presented high protein levels and, in addition, provided remarkable amounts of phytochemicals such as dietary fibre, polyphenols, flavonoids and carotenoids. Some of the investigated genotypes, such as Senatore Cappelli, Solex, Svevo and Orobel, emerged with intriguing nutritional and phytochemical profiles, with the highest levels of dietary fibre and antioxidant compounds. The study provided the basis for further investigations into the adaptability of the durum wheat genotypes to low input management, for the selection of genotypes characterised by higher yield and valuable nutrient and nutraceutical quality

Multiscale Bone Remodelling with Spatial P Systems

Many biological phenomena are inherently multiscale, i.e. they are characterized by interactions involving different spatial and temporal scales simultaneously. Though several approaches have been proposed to provide "multilayer" models, only Complex Automata, derived from Cellular Automata, naturally embed spatial information and realize multiscaling with well-established inter-scale integration schemas. Spatial P systems, a variant of P systems in which a more geometric concept of space has been added, have several characteristics in common with Cellular Automata. We propose such a formalism as a basis to rephrase the Complex Automata multiscaling approach and, in this perspective, provide a 2-scale Spatial P system describing bone remodelling. The proposed model not only results to be highly faithful and expressive in a multiscale scenario, but also highlights the need of a deep and formal expressiveness study involving Complex Automata, Spatial P systems and other promising multiscale approaches, such as our shape-based one already resulted to be highly faithful.Comment: In Proceedings MeCBIC 2010, arXiv:1011.005

Histomorphological analysis of the effect of rigid fixation on growing sutures in the rabbit

The effect of internal rigid fixation (IRF) on bone growth was studied in an experimental model set up in the rabbit. The frontonasal suture of the right side was surgically bridged by a microplate. As reference for bone growth, four screws were placed symmetrically in the four bony segments including the frontonasal suture on both sides. The suture development was followed dynamically for 40 days on the basis of the position of the screws established radiographically. The rate of bone formation along the sutural bones was evaluated by means of the tetracycline labelling technique. The structure of the newly formed bone and its degree of mineralization were respectively analysed under polarized light and with microradiography. It was demonstrated that IRF prevents growth of the sutural membrane but not of the osteogenic process; as a consequence the constrained sutures soon undergo synostosis. This fact must be taken into consideration when IRF is employed in children in order to avoid delayed removal of the plate irreversibly stopping the growth of the constrained suture

Differential Regulation of G Protein α Subunit Trafficking by Mono- and Polyubiquitination

Previously we used mass spectrometry to show that the yeast G protein alpha subunit Gpa1 is ubiquitinated at Lys-165, located within a subdomain not present in other G alpha proteins (Marotti, L. A., Jr., Newitt, R., Wang, Y., Aebersold, R., and Dohlman, H. G. (2002) Biochemistry 41, 5067-5074). Here we describe the functional role of Gpa1 ubiquitination. We find that Gpa1 expression is elevated in mutants deficient in either proteasomal or vacuolar protease function. Vacuolar protease pep4 mutants accumulate monoubiquitinated Gpa1, and much of the protein is localized within the vacuolar compartment. In contrast, proteasome-defective rpt6/cim3 mutants accumulate polyubiquitinated Gpa1, and in this case the protein exhibits cytoplasmic localization. Cells that lack Ubp12 ubiquitin-processing protease activity accumulate both mono- and polyubiquitinated forms of Gpa1. In this case, Gpa1 accumulates in both the cytoplasm and vacuole. Finally, a Gpa1 mutant that lacks the ubiquitinated subdomain remains unmodified and is predominantly localized at the plasma membrane. These data reveal a strong relationship between the extent of ubiquitination and trafficking of the G protein alpha subunit to its site of degradation

Comparison of Molecular Phenotypes of Ductal Carcinoma In Situ and Invasive Breast Cancer

Introduction: At least four major categories of invasive breast cancer that are associated with different clinical outcomes have been identified by gene expression profiling: luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) and basal-like. However, the prevalence of these phenotypes among cases of ductal carcinoma in situ (DCIS) has not been previously evaluated in detail. The purpose of this study was to compare the prevalence of these distinct molecular subtypes among cases of DCIS and invasive breast cancer. Methods: We constructed tissue microarrays (TMAs) from breast cancers that developed in 2897 women enrolled in the Nurses' Health Study (1976 to 1996). TMA slides were immunostained for oestrogen receptor (ER), progesterone receptor (PR), HER2, cytokeratin 5/6 (CK5/6) and epidermal growth factor receptor (EGFR). Using these immunostain results, cases were grouped into molecularly defined subtypes. Results: The prevalence of the distinct molecular phenotypes differed significantly between DCIS (n = 272) and invasive breast cancers (n = 2249). The luminal A phenotype was significantly more frequent among invasive cancers (73.4%) than among DCIS lesions (62.5%) (p = 0.0002). In contrast, luminal B and HER2 molecular phenotypes were both more frequent among DCIS (13.2% and 13.6%, respectively) as compared with invasive tumours (5.2% and 5.7%, respectively) (p < 0.0001). The basal-like phenotype was more frequent among the invasive cancers (10.9%) than DCIS (7.7%), although this difference was not statistically significant (p = 0.15). High-grade DCIS and invasive tumours were more likely to be HER2 type and basal-like than low- or intermediate-grade lesions. Among invasive tumours, basal-like and HER2 type tumours were more likely to be more than 2 cm in size, high-grade and have nodal involvement compared with luminal A tumours. Conclusion: The major molecular phenotypes previously identified among invasive breast cancers were also identified among cases of DCIS. However, the prevalence of the luminal A, luminal B and HER2 phenotypes differed significantly between DCIS and invasive breast cancers

Efficacy of Chlorine-based, Enzymatic and Combined Chlorine-enzyme Treatments on Biofilm Removal

Glyphosate resistance evolution in weeds is a growing problem in world agriculture. Here, we have investigated the mechanism(s) of glyphosate resistance in a Lolium rigidum population (DAG1) from South Africa. Nucleotide sequencing revealed the existence of at least three EPSPS homologues in the L. rigidum genome and identified a novel proline 106 to leucine substitution (P106L) in 52% DAG1 individuals. This mutation conferred a 1.7-fold resistance increase to glyphosate at the whole plant level. Additionally, a 3.1-fold resistance increase, not linked to metabolism or translocation, was estimated between wild-type P106-DAG1 and P106-STDS sensitive plants. Point accepted mutation analysis suggested that other amino acid substitutions at EPSPS position 106 are likely to be found in nature besides the P106/S/A/T/L point mutations reported to date. This study highlights the importance of minor mechanisms acting additively to confer significant levels of resistance to commercial field rates of glyphosate in weed populations subjected to high selection pressure