One-loop effective potential in M4 x T2 with and without 't Hooft flux

We review the basic notions of compactification in the presence of a background flux. In extra-dimentional models with more than five dimensions, Scherk and Schwarz boundary conditions have to satisfy 't Hooft consistency conditions. Different vacuum configurations can be obtained, depending whether trivial or non-trivial 't Hooft flux is considered. The presence of the "magnetic" background flux provide, in addition, a mechanism for producing four-dimensional chiral fermions. Particularizing to the six-dimensional case, we calculate the one-loop effective potential for a U(N) gauge theory on M4 x T2. We firstly review the well known results of the trivial 't Hooft flux case, where one-loop contributions produce the usual Hosotani dynamical symmetry breaking. Finally we applied our result for describing, for the first time, the one-loop contributions in the non-trivial 't Hooft flux case

Innovative strategy for polyhydroxyalkanoates recovery from mixed microbial cultures. Effects of aqueous phase and solvent extraction on polymer properties

This work aimed to investigate various methods of polyhydroxyalkanoates (PHA) extraction and to optimize the recovery in the view of reducing solvents’ use and waste. The extraction tests were applied on PHA-rich biomass collected at the end of the accumulation step, conducted both at pilot and lab scale. PHA-rich biomass obtained from the lab scale process was produced from synthetic feedstock (mixture of acetic and propionic acids), while fermented organic waste was used for PHA production at pilot scale. In the extraction tests, different solutions of NaOH, also in combination with a surfactant (sodium dodecyl sulfate, SDS), were used to recover the polymer from the non-polymeric cellular material (NPCM). Different times (3, 6 and 24 h) and concentrations (0.05 – 1 M) were tested, evaluating also the effect of adding SDS (0.1 % w/v). As a benchmark, solvent extraction with chloroform and oxidation with NaClO were also conducted. Finally, extracted samples were characterized through several techniques: DSC, TGA, GC-FID, capillary viscosimetry. Alkaline treatment at short times and low concentrations resulted to be more efficient in terms of purity (85 – 99 % w/w PHA) and recovery (higher than 80 % w/w), than higher concentration. On the other hand, the presence of SDS had dramatic effects on the recovery (lower than 50 % w/w) and also on the molecular weight, which was two folds lower than that obtained from alkaline extraction. Overall, extraction with aqueous phase reagents had no effects on thermal properties, which resulted to be in the range of those reported in literature

In-vivo evaluations of bone regenerative potential of two novel bioactive glasses

: Due to the aging of population, materials able to repair damaged tissues are needed. Among others, bioactive glasses (BGs) have attracted a lot of interest due to their outstanding properties both for hard and soft tissues. Here, for the first time, two new BGs, which gave very promising results in preliminary in vitro-tests, were implanted in animals in order to evaluate their regenerative potential. The new BGs, named BGMS10 and Bio_MS and containing specific therapeutic ions, were produced in granules and implanted in rabbits' femurs for up to 60 days, to test their biocompatibility and osteoconduction. Additionally, granules of 45S5 Bioglass® were employed and used as a standard reference for comparison. The results showed that, after 30 days, the two novel BGs and 45S5 displayed a similar behavior, in terms of bone amount, thickness of new bone trabeculae and affinity index. On the contrary, after 60 days, 45S5 granules were mainly surrounded by wide and scattered bone trabeculae, separated by large amounts of soft tissue, while in BGMS10 and Bio_MS the trabeculae were thin and uniformly distributed around the BG granules. This latter scenario could be considered as more advantageous, since the features of the two novel BG granules allowed for the neo-formation of a uniformly distributed bony trabeculae, predictive of more favorable mechanical behavior, compared to the less uniform coarse trabeculae, separated by large areas of soft tissue in 45S5 granules. Thus, BGMS10 and Bio_MS could be considered suitable products for tissue regeneration in the orthopedic and dental fields.Due to the aging of population, materials able to repair damaged tissues are needed. Among others, bioactive glasses (BGs) have attracted a lot of interest due to their outstanding properties both for hard and soft tissues. Here, for the first time, two new BGs, which gave very promising results in preliminary in vitro-tests, were implanted in animals in order to evaluate their regenerative potential. The new BGs, named BGMS10 and Bio_MS and containing specific therapeutic ions, were produced in granules and implanted in rabbits' femurs for up to 60 days, to test their biocompatibility and osteoconduction. Additionally, granules of 45S5 Bioglass® were employed and used as a standard reference for comparison. The results showed that, after 30 days, the two novel BGs and 45S5 displayed a similar behavior, in terms of bone amount, thickness of new bone trabeculae and affinity index. On the contrary, after 60 days, 45S5 granules were mainly surrounded by wide and scattered bone trabeculae, separated by large amounts of soft tissue, while in BGMS10 and Bio_MS the trabeculae were thin and uniformly distributed around the BG granules. This latter scenario could be considered as more advantageous, since the features of the two novel BG granules allowed for the neo-formation of a uniformly distributed bony trabeculae, predictive of more favorable mechanical behavior, compared to the less uniform coarse trabeculae, separated by large areas of soft tissue in 45S5 granules. Thus, BGMS10 and Bio_MS could be considered suitable products for tissue regeneration in the orthopedic and dental fields

The Khartoum-Omdurman conurbation : a growing megacity at the confluence of the Blue and White Nile Rivers

Khartoum is one of the largest cities in Africa, located immediately south of the junction of the Blue and White Nile rivers in central Sudan. The growth of the Greater Khartoum-Omdurman conurbation arose \uac\u2013 without a proper urban plan \u2013 from the agricultural wealth created through the completion of three major dams in 1925, 1937 and 1966, and mostly in the last three decades. Urban expansion was enabled by and helped to enhance the major agricultural expansion of the Gezira clay plains located to the south between the lower Blue and White Nile rivers. The confluence of the Blue and White Nile has been a focus of human settlement for at least 8,000 years, initially by semi-sedentary groups with a fishing-hunting-gathering lifestyle and later by Neolithic groups as shown by hundreds of archaeological sites. Today, Khartoum is a desert city and the hottest capital city on Earth, still very vulnerable to floods triggered by intense convectional storms. Such extreme events may become more common in future, representing a major geomorphological hazard in a city developed without urban plans. Moreover, uncontrolled urban and agricultural development is threatening most of the prehistoric cultural heritage of the region

Next-to-leading-order QCD Corrections to Higgs Production in association with a Jet

We compute the next-to-leading-order (NLO) QCD corrections to the Higgs pT distribution in Higgs production in association with a jet via gluon fusion at the LHC, with exact dependence on the mass of the quark circulating in the heavy-quark loops. The NLO corrections are presented including the top-quark mass, and for the first time, the bottom-quark mass as well. Further, besides the on-shell mass scheme, we consider for the first time a running mass renormalisation scheme. The computation is based on amplitudes which are valid for arbitrary heavy-quark masses.Comment: LaTeX, 7 pages, 5 figure

Guest or pest? Spatio-temporal occurrence and effects on soil and vegetation of the wild boar on the Elba island

In areas where allochthonous large mammals, such as the wild boars (Sus scrofa), occur in high density, human-wildlife conflicts may arise. In these contexts, assessing spatio-temporal patterns of the introduced population is paramount to its management. Here, we studied wild boars in the Elba island, Italy, where they have been introduced and are perceived as pests. While crop-raiding has been documented, no studies addressed the spatio-temporal occurrence, nor the impact of foraging on natural habitat. We surveyed the Western part of the island with three camera trapping surveys within one year. We found that the species' estimated occupancy probability was higher in summer-autumn (0.75±0.14) and winter-early spring (0.70±0.10) than in late spring-summer (0.53±0.15), whereas detection probability did not vary. Occupancy was significantly associated with elevation and vegetation cover, with preference for lower elevation and woodland. The lower site use of wild boars during spring-summer might reflect lower food availability in this season, and/or movements towards landfarms outside the sampled area. Detectability increased with proximity to roads during spring-summer and decreased with humans' relative abundance in the other periods. Moreover, boars were mainly nocturnal, with an overlap with human activity that decreased when human presence was higher. Combined, these suggest behavioural avoidance of human disturbance by boars. We also evaluated the impact of boars' foraging on the soil and vegetation and found that it was higher in pine plantations than other covers, however, it was not associated with variation in boars' occupancy across habitats. Our results indicate that the spatio-temporal activity of wild boars on Elba island appears driven by seasonal preferences for food-rich cover and avoidance of human disturbance. The lowered site use in months with lower resources could partially reflect increased proximity to settled and farmed areas, which may, in turn, trigger crop-raiding and hence the negative perception by residents

An overview on the primary factors that contribute to non-allergic asthma in children

The prevalence of non-allergic asthma in childhood is low, peaking in late adulthood. It is triggered by factors other than allergens, like cold and dry air, respiratory infections, hormonal changes, smoke and air pollution. In the literature, there are few studies that describe non-allergic asthma in pediatric age. Even though it is a less common disorder in kids, it is crucial to identify the causes in order to keep asthma under control, particularly in patients not responding to conventional treatments. In this review, we discuss non-IgE-mediated forms of asthma, collecting the latest research on etiopathogenesis and treatment

Riflettanza di superfici vulcaniche:la campagna 2003 sul Monte Etna

The results obtained in Mt. Etna spectroradiometric field survey of June 2003 are presented and discussed. The goal of the survey was the analysis of the reflectance properties of the young pyroclastic deposits produced after the effusive activity of 2002-2003 and of the older lava flows. To achieve this goal, a template was created in order to organize the field data collected in a number of selected sites characterised by different surface materials. The results show that reflectance of pyroclastic flows is always very low and constant, besides grain size and composition of the flow. Pahoehoe units show higher reflectance values, even though the spectral characterisation of the older lava flows must take into account weathering products and vegetation coverage