The small xx behavior of the gluon structure function from total cross sections

Within a QCD-based eikonal model with a dynamical infrared gluon mass scale we discuss how the small $x$ behavior of the gluon distribution function at moderate $Q^{2}$ is directly related to the rise of total hadronic cross sections. In this model the rise of total cross sections is driven by gluon-gluon semihard scattering processes, where the behavior of the small $x$ gluon distribution function exhibits the power law $xg(x,Q^2)= h(Q^2)x^{-\epsilon}$. Assuming that the $Q^{2}$ scale is proportional to the dynamical gluon mass one, we show that the values of $h(Q^2)$ obtained in this model are compatible with an earlier result based on a specific nonperturbative Pomeron model. We discuss the implications of this picture for the behavior of input valence-like gluon distributions at low resolution scales.Comment: 19 pages, 3 figures; revised version; to appear in Int. J. Mod. Phys.

Quantitative real-time polymerase chain reaction (QPCR) assay as a molecular tool to assess rickettsial replications in tick hosts

During the past century, many species of the Spotted Fever Group Rickettsia (SFGR)have been described, especially, through the introduction of a variety of molecular techniques applied to detect rickettsiae inside of their host. In this study we developed a quantitative realtime polymerase chain reaction (qPCR) assay (1) to characterize the growth and the distribution of a SFGR of unrecognized pathogenicity in naturally infected Amblyomma americanum ticks during physiological events; and (2) to terminate the influence of the host cell specificity in the replication patterns of recognized and unrecognized SFGR during a reciprocal rickettsiae challenge in both mammalian and tick cell lines. Rickettsia amblyommii was identified in the tissue samples of naturally infected A. americanum ticks at ratios of ¡Ü 1 rickettsiae per tick cell. Significant variability in the ratio of ickettsial to tick gene copy numbers between the tissues was identified; however, no single tissue was consistently observed to have the greatest rickettsial burden throughout the feeding event. Furthermore, the ratio of rickettsial to tick gene copy numbers did not significantly differ between eggs, immature ticks, and feeding events. In the in vitro study, differences in the ratio of rickettsiae per cell were observed within each cell line. The ratio of rickettsiae per host cell was greatest in Rickettsia-infected ISE6 cells, compared to Vero cells. Rickettsia parkeri infection load was consistently greater in both cell lines compared to R. amblyommii and Rickettsia montanensis; and considerable variability between these last two Rickettsia species was observed when the ratio of ickettisae per host cell was calculated for each individual cell line. The implications of the use of this technique to understand the pathogenic nature of some SFGR and to investigate the host specificity in the tick-SFGR interactions is further presented and discussed

Characterization of Novel Akermanite:Poly-E-Caprolactone Scaffolds for Bone Tissue Engineering Aapplications Combined with Human Adipose-Derived Stem Cells

The development of porous materials useful as scaffolds for the sustained three-dimensional (3D) growth of human adipose-derived stem cells (hASC) is of particular interest to facilitate healing after musculoskeletal injuries. In this study, a composite porous material obtained by blending akermanite with poly-e-caprolactone (PCL) is proposed as novel alternative to bone tissue regeneration. The objectives of this study are (1) to characterize the akermanite:PCL scaffold properties; (2) to investigate the in vitro osteogenic potential of hASC loaded to optimal akermanite:PCL scaffolds; (3) to assess the metabolic activity and osteogenesis of hASC loaded to optimal akermanite:PCL scaffolds post-thawing using optimal cryopreservation protocol; and (4) to evaluate the behavior of optimal akermanite:PCL scaffolds in vivo using an immunodeficient murine model for ectopic bone formation. We hypothesized that (1) optimal akermanite:PCL blend has mechanical properties and biocompatibility suitable for tissue engineering applications; (2) hASC loaded to optimal akermanite:PCL scaffolds has higher expression of mature osteogenic marker in scaffolds cultured in osteogenic medium for 21 days; (3) PVP-serum free medium can be used to cryopreserve hASC loaded to optimal akermanite:PCL scaffolds; and (4) hASC preloaded to optimal akermanite:PCL scaffolds would produce meaningful bone-like tissue 8 weeks post-implantation. According to the results, 75:25 akermanite:PCL composite scaffolds displayed increased mechanical (1), biological and osteogenic properties (1-3). Moreover, hASC loaded to 75:25 akermanite:PCL scaffolds and frozen at 40ᵒC/min displayed metabolic activity and osteogenesis comparable to fresh control scaffolds (3). However, in vivo implantation of akermanite-base scaffolds (akermanite and akermanite:PCL) in nude mice, sudden death within the first 48 hours of this study (4). The acute toxicity observed in all animals assigned to the akermanite scaffolds was associated to a disturbance of the phosphorus homeostasis in vivo. Specifically, akermanite and akermanite:PCL scaffolds harvested 48 hours post-implantation had comparable levels of phosphorous in the composition, indicating acute phosphorous depletion from the serum. Accumulative evidences have suggested that akermanite is biocompatible and can enhance adhesion, proliferation and osteogenic phenotype maintenance of adult/osteoprogenitor stem cells both in vitro and in vivo. As a conclusion, further studies are needed to address the akermanite dose-dependent toxicity in murine models for akermanite-assisted bone regeneration

Philosophy and childhood: theory and practice

An introduction to the Special Issu

Specializzazione produttiva e crescita: un'analisi mediante indicatori

Il paper analizza l\u2019evoluzione dei percorsi della specializzazione produttiva dell\u2019Italia e dei suoi principali partner commerciali (Francia, Germania e Stati Uniti). Nella sezione metodologica, \ue8 discussa l\u2019efficacia dell\u2019indice di Lafay quale indicatore di specializzazione. In tale prospettiva si propongono alcune modifiche ed integrazioni rispetto alla sua espressione originale, al fine di individuare aspetti specifici riferiti alla teoria dei vantaggi comparati. Si discutono infine alcune implicazioni empiriche, che confermano la specializzazione della manifattura italiana in settori low-tech; esse mostrano come, a differenza di gran parte degli altri Paesi sviluppati, l\u2019Italia sia specializzata in settori scarsamente coinvolti nell\u2019attuale tendenza verso la globalizzazione dei sistemi economici

Gene expression profiling of Mycobacterium avium subsp. paratuberculosis in simulated multi-stress conditions and within THP-1 cells reveals a new kind of interactive intramacrophage behaviour

Recent studies have identified in Mycobacterium avium subsp. paratuberculosis (MAP), already known as a pathogen in ruminants, a potential zoonotic agent of some autoimmune diseases in humans. Therefore, considering the possible risk for public health, it is necessary a thorough understanding of MAP's gene expression during infection of human host as well as the identification of its immunogenic and/or virulence factors for the development of appropriate diagnostic and therapeutic tools.In order to characterize MAP's transcriptome during macrophage infection, we analyzed for the first time the whole gene expression of a human derived strain of MAP in simulated intraphagosomal conditions and after intracellular infection of the human macrophage cell line THP-1 by using the DNA-microarray technology. Results showed that MAP shifts its transcriptome to an adaptive metabolism for an anoxic environment and nutrient starvation. It up-regulates several response factors to oxidative stress or intracellular conditions and allows, in terms of transcription, a passive surface peptidoglycan spoliation within the macrophage along with an intensification of the anabolic activity for lipidic membrane structures.These results indicate a possible interactive system between MAP and its host cell based on the internal mimicry unlike other intracellular pathogens, bringing new hypothesis in the virulence and pathogenicity of MAP and its importance in human health

Foundry wastes reuse and recycling in concrete production

The industrial process of a cast iron foundry plant located in the North of Italy was analyzed in order to determine the amount and kind of produced wastes. The main fractions are core and moulding sands, muds and powders from dust abatement plants, furnace and ladle slags, and exhaust lime, making about 750-800 t/d of residues for a production of about 800 t/d of globular and grey cast iron. All wastes were sampled and characterized by means of particle-size distribution and chemical analyses to evaluate the best reuse and recycling solutions. On the grounds of the gathered results, the residues may be divided in three categories according to the particle-size dimensions: below 0.1 mm, between 0.1 and 0.6 mm and above 0.6 mm. The fraction above 0.6 mm, mainly made of metallic iron, may be reused in the furnaces. The fraction between 0.1 mm and 0.6 mm may be reused in cores production, after a regeneration treatment. The fraction between 0.1 and 0.025 mm may be recycled as raw material for the concrete industry, and the below 0.025 mm fraction may be reused in green moulding operations. An economic evaluation of the proposed reuse and recycling solutions was performed

Estimating general equilibrium models: an application with labour market frictions

This handbook shows how to set up, approximate, and estimate a standard real business cycle model enriched with labour market frictions. The structural equations of the model are derived by maximizing the agents’ objective function subject to the structure of the economy. Given the complexity of the resulting equations, we show how to approximate the model around its long-run equilibrium. We then use the approximated equations to take the model to the data and estimate it using Bayesian techniques. To perform the analysis we use a simple real business cycle model for two reasons. First, due to its simplicity, we can primarily focus on the modelling and estimation techniques; second, this simple framework constitutes the backbone model on which central banks build microfounded models to support the policy analysis. A series of forthcoming Handbooks will document how to enrich this simple framework. To motivate the exercise we start from recent empirical evidence suggesting that a positive technology shock leads to a decline in labour inputs. The standard real business model fails to account for this empirical regularity. The question we analyze in this handbook is whether the presence of labour market frictions addresses this problem, without otherwise altering the functioning of the standard model. To this end, we develop and estimate a real business cycle model using Bayesian techniques that allows, but does not require, labour market frictions to generate a negative response of employment to a technology shock. The results of the estimation support the hypothesis that labour market frictions are the factor responsible for the negative response of employment. Given the pedagogical nature of this handbook, we provide documentation of the MATLAB codes used to implement the modelling and estimation techniques described. To make the programming simple, we used Dynare version 3. We thank Michel Juillard for making his routines publicly available.Estimating;general; equilibrium; models;application;labour; market; frictions

X, Y and Z States

Many new states in the charmonium mass region were recently discovered by BaBar, Belle, CLEO-c, CDF, D0, BESIII, LHCb and CMS Collaborations. We use the QCD Sum Rule approach to study the possible structure of some of these states.Comment: Contribution for the proceedings of the "XII Quark Confinement and the Hadron Spectrum - CONF12" conferenc