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.

MRSA screening by the Xpert MRSA PCR assay: pooling samples of the nose, throat, and groin increases the sensitivity of detection without increasing the laboratory costs.

The performance of the Xpert MRSA polymerase chain reaction (PCR) assay on pooled nose, groin, and throat swabs (three nylon flocked eSwabs into one tube) was compared to culture by analyzing 5,546 samples. The sensitivity [0.78, 95 % confidence interval (CI) 0.73-0.82] and specificity (0.99, 95 % CI 0.98-0.99) were similar to the results from published studies on separated nose or other specimens. Thus, the performance of the Xpert MRSA assay was not affected by pooling the three specimens into one assay, allowing a higher detection rate without increasing laboratory costs, as compared to nose samples alone

Una via per tornare allo sviluppo: rendersi indispensabili nella rete

L’articolo esamina le potenzialità di crescita dell’industria italiana, al fine di individuare una miglior destinazione delle risorse disponibili per la ricerca. Il contributo ruota attorno a due temi centrali: in primo luogo, nell’attuale scenario economico internazionale, la produzione di beni e servizi di maggior valore è prioritaria rispetto alla necessità di abbattimento dei costi di produzione; in secondo luogo, considerato il crescente ruolo delle catene di fornitura nella produzione dei beni di contenuto tecnologicamente avanzato, lo sviluppo economico di un determinato territorio richiede la specializzazione in alcuni dei nodi della rete di fornitura più che non la presenza in tutte le sue fasi. Ne discende l’obiettivo di rendersi indispensabili in quegli anelli del processo di produzione che manifestano rilevanti prospettive di crescita. Il concetto di indispensabilità, con le sue ripercussioni sul benessere, viene analizzato mediante appositi modelli teorici. Vengono poi predisposti indicatori economico-statistici in grado di cogliere l’idea di indispensabilità, e di misurarne il livello per vari settori dell’economia italiana. Sulla base dei risultati dell’analisi, si derivano le implicazioni di policy in relazione all’allocazione dei contributi pubblici alla ricerc

Adult native septic arthritis: a review of 10 years of experience and lessons for empirical antibiotic therapy.

Objectives To review the epidemiology of native septic arthritis to establish local guidelines for empirical antibiotic therapy as part of an antibiotic stewardship programme. Methods We conducted a 10 year retrospective study based on positive synovial fluid cultures and discharge diagnosis of septic arthritis in adult patients. Microbiology results and medical records were reviewed. Results Between 1999 and 2008, we identified 233 episodes of septic arthritis. The predominant causative pathogens were methicillin-susceptible Staphylococcus aureus (MSSA) and streptococci (respectively, 44.6% and 14.2% of cases). Only 11 cases (4.7%) of methicillin-resistant S. aureus (MRSA) arthritis were diagnosed, among which 5 (45.5%) occurred in known carriers. For large-joint infections, amoxicillin/clavulanate or cefuroxime would have been appropriate in 84.5% of cases. MRSA and Mycobacterium tuberculosis would have been the most frequent pathogens that would not have been covered. In contrast, amoxicillin/clavulanate would have been appropriate for only 75.3% of small-joint infections (82.6% if diabetics are excluded). MRSA and Pseudomonas aeruginosa would have been the main pathogens not covered. Piperacillin/tazobactam would have been appropriate in 93.8% of cases (P < 0.01 versus amoxicillin/clavulanate). This statistically significant advantage is lost after exclusion of diabetics (P = 0.19). Conclusions Amoxicillin/clavulanate or cefuroxime would be adequate for empirical coverage of large-joint septic arthritis in our area. A broad-spectrum antibiotic would be significantly superior for small-joint infections in diabetics. Systematic coverage of MRSA is not justified, but should be considered for known carriers. These recommendations are applicable to our local setting. They might also apply to hospitals sharing the same epidemiology

New Forms of Government Intervention in the Era of Global Imbalances

The paper illustrates how the Government role has recently evolved, specifically focusing on the 2008 financial crisis. First, we analyze the Government responsibilities in triggering the crisis, by bloating the supply of credit. We discuss emerging countries\u2019 expansionary monetary policy, in many cases aimed at defending their export, thereby directing huge savings flows towards developed countries. We then expound the role of the US housing and monetary policies, as well as other countries\u2019 policies, particularly regarding financial deregulation. Second, we deal with some critical aspects of Governments\u2019 intervention in the aftermath of the crisis. We show the negative impact of a number of policies, particularly in the accounting field, which contributed to exacerbating the tendency to an inefficient allocation of the available capital, where an excessive weight has been placed on low-risk assets, resulting in a slowdown of economic growth. Finally, we use a simple game theoretic model to emphasize the need for an internationally coordinated financial regulation policy

Relazioni verticali e organizzazione d’impresa: nuove tematiche sul fronte dell’oligopolio

Il saggio analizza lo sviluppo recente dei modelli di oligopolio in riferimento alle strutture verticali, caratterizzati, cioè, da una filiera di produzione organizzata in diversi stadi successivi

Watershed Segmentation of Medical Volumes with Paint Drop Marking

We present an improvement of the classical marker-controlled watershed approach in the direction of a better exploitation of user-defined markers. The combined action of a partial flooding and paint drops falling downwards on the gray value relief from marker locations, leads to a robust and meaningful identification of the candidate basins, which is a prerequisite for an accurate segmentation. This is useful for user-controlled segmentation of biomedical volumes in that it facilitates robust identification of complex 3D structures with inhomogeneous borders. To this end, a visual interactive segmentation system has been implemented where different user-data interaction tools can be selected by physicians to generate machine-understandable knowledge in a quick and compact way. Experimental results on selected use-cases demonstrate the strengths of the proposed solutions