Interplay of network dynamics and ties heterogeneity on spreading dynamics

The structure of a network dramatically affects the spreading phenomena unfolding upon it. The contact distribution of the nodes has long been recognized as the key ingredient in influencing the outbreak events. However, limited knowledge is currently available on the role of the weight of the edges on the persistence of a pathogen. At the same time, recent works showed a strong influence of temporal network dynamics on disease spreading. In this work we provide an analytical understanding, corroborated by numerical simulations, about the conditions for infected stable state in weighted networks. In particular, we reveal the role of heterogeneity of edge weights and of the dynamic assignment of weights on the ties in the network in driving the spread of the epidemic. In this context we show that when weights are dynamically assigned to ties in the network an heterogeneous distribution is able to hamper the diffusion of the disease, contrary to what happens when weights are fixed in time.Comment: 10 pages, 10 figure

Modeling the effects of variable feeding patterns of larval ticks on the transmission of Borrelia lusitaniae and Borrelia afzelii

Spirochetes belonging to the Borrelia burgdoferi sensu lato (sl) group cause Lyme Borreliosis (LB), which is the most commonly reported vector-borne zoonosis in Europe. B. burgdorferi sl is maintained in nature in a complex cycle involving Ixodes ricinus ticks and several species of vertebrate hosts. The transmission dynamics of B. burgdorferi sl is complicated by the varying competence of animals for different genospecies of spirochetes that, in turn, vary in their capability of causing disease. In this study, a set of difference equations simplifying the complex interaction between vectors and their hosts (competent and not for Borrelia) is built to gain insights into conditions underlying the dominance of B. lusitaniae (transmitted by lizards to susceptible ticks) and the maintenance of B. afzelii (transmitted by wild rodents) observed in a study area in Tuscany, Italy. Findings, in agreement with field observations, highlight the existence of a threshold for the fraction of larvae feeding on rodents below which the persistence of B. afzelii is not possible. Furthermore, thresholds change as nonlinear functions of the expected number of nymph bites on mice, and the transmission and recovery probabilities. In conclusion, our model provided an insight into mechanisms underlying the relative frequency of different Borrelia genospecies, as observed in field studies.Comment: 14 pages, 3 figures, to be published in Theoretical Population Biolog

I.S.Mu.L.T. Achilles Tendon Ruptures Guidelines

This work provides easily accessible guidelines for the diagnosis, treatment and rehabilitation of Achilles tendon ruptures. These guidelines could be considered as recommendations for good clinical practice developed through a process of systematic review of the literature and expert opinion, to improve the quality of care for the individual patient and rationalize the use of resources. This work is divided into two sessions: 1) questions about hot topics; 2) answers to the questions following Evidence Based Medicine principles. Despite the frequency of the pathology andthe high level of satisfaction achieved in treatment of Achilles tendon ruptures, a global consensus is lacking. In fact, there is not a uniform treatment and rehabilitation protocol used for Achilles tendon ruptures

Immunobiologic and Antiinflammatory Properties of a Bark Extract from Ampelozizyphus amazonicus Ducke

Ampelozizyphus amazonicus is used in the treatment and prevention of malaria. The effect of an aqueous extract from this plant (SART) on the immune response was investigated by measuring immunoglobulin production induced by immunization with the antigen TNP-Ficoll in Plasmodium chabaudi-infected mice. SART treatment increased antigen-specific IgM and IgG levels in TNPFicoll-immunized mice. The B cell response during malarial infection was also modified by SART. There was an increase in total serum IgM and IgG and a decrease in the percentage of splenic plasma cells (CD138+ cells) in P. chabaudi-infected, SART-treated animals. SART (1, 3 or 10 mg/kg, p.o.) and the reference drug dexamethasone (5 mg/kg) were also tested in carrageenan-induced leukocyte migration to the subcutaneous air pouch (SAP). All SART doses significantly reduced leukocyte migration into the SAP. The protein concentration resulting from extravasation into the peritoneum was also significantly reduced. Our data indicate that SART possesses immunomodulatory properties, inducing an in vivo modification of the B lymphocyte response and antiinflammatory properties, which are partly due to a reduction in cell migration and are most likely due to an inhibition of the production of inflammatory mediators. Preliminary HPLC-ESI-MS/MS analysis of SART shows a complex saponin profile with deprotonated molecule [M-H] − ions in the range of m/z 800-1000

The effect of shear flow on microreactor clogging

Solid handling is a key issue in microreactors where clogging problems can be severe due to confined flow conditions. Here, microreactor clogging is investigated in a Buchwald–Hartwig C–N cross-coupling reaction of amines with organohalides important in the pharmaceutical and fine chemicals industries for the production of aromatic amines. The reaction takes place in a tubular stainless steel continuous-flow reactor and generates solid particles by precipitation of potassium bromide in the continuous phase. The reactor output is fed to a glass microchannel where the flowing particles are imaged by on-line high-speed video microscopy. It is found that KBr particles adhere to the channel wall and aggregate into clusters, eventually leading to channel clogging. The effect of flow is studied by setting the Reynold number (Re) at 1.5 and 15. At Re =1.5 cluster growth is faster and less dense, dendritic structures made of needle-like crystals are observed. At Re =15, cluster growth is slower and more compact structures of spherical shape are found. Clogging time is faster at Re =15. These results can be explained by the interplay between flow-induced interactions and particle-wall and particle-particle attractive forces. Since cluster formation starts at the wall, the insight provided by this work, although obtained in a microfluidic geometry, can be applied more generally to the problem of fouling in continuous flow reacting systems

The biological respect of the posterolateral bundle in ACL partial injuries. Retrospective analysis of 2 different surgical management of ACL partial tear in a population of high-demanding sport patients

Introduction: Most of the techniques described in the literature for the repair of chronic partial ACL tears do not spare the intact portion of the ligament. Aim of this study was to perform a retrospective analysis of the results obtained from the same ACL reconstructive surgical technique applicated by sparing or not AM bundle in a population of 42 sports patients. Materials and methods: From 2010 to 2012, 42 patients who suffered ACL partial tear injury with rupture of posterolateral bundle were randomly divided in two groups homogenous for sex, age and sport-level activities. The first group with 22 patients performed ACL reconstruction with ST-GR over-the-top technique sacrificing the anteromedial (Removing AMT Group) remaining bundle intact; otherwise, the second group with 20 patients performed the same ACL reconstruction using only ST and maintaining AM bundle (Sparing AMT Group). All the patients were followed up by MRI evaluation at 12\ua0months and clinical evaluation with IKDC score, Tegner score at 6, 12, 24, 36, 48 and 60\ua0months. KT-1000 instrument was performed at 12\ua0months. The results were analyzed statistically to evaluate differences between the two groups in terms of subjective outcome, and stability and for all the tests P < 0.05 was considered significant. Results: We did not observe any failure at final follow-up. IKDC subjective score at final follow-up in Removing AMT Group was 91.2 \ub1 2.3 in Sparing AMT Group was 92.4 \ub1 2.7. Tegner score at final follow-up was 7.2 \ub1 2.1 for Removing AMT Group and 7.8 \ub1 1.8 for Sparing AMT Group. Arthrometric evaluation performed with KT-1000 at final follow-up showed a side-to-side difference of 0.9 \ub1 1.3\ua0mm in the Removing AMT Group against 0.8 \ub1 1.0\ua0mm in the Sparing AMT Group. Return time to the sport was 7.1\ua0months for Removing AMT Group otherwise 6.1\ua0months for the Sparing AMT Group. Conclusions: Both the described techniques in this study demonstrated to be able to guarantee a successful outcome. However, although no statistically significant differences were evident in terms of subjective and objective outcome between these techniques some evident benefits were evident using the sparing bundle technique in Sparing AMT Group such as better clinical scores at the final follow-up and an earlier return to sport activity