Finite-momentum Bose-Einstein condensates in shaken 2D square optical lattices

We consider ultracold bosons in a 2D square optical lattice described by the Bose-Hubbard model. In addition, an external time-dependent sinusoidal force is applied to the system, which shakes the lattice along one of the diagonals. The effect of the shaking is to renormalize the nearest-neighbor hopping coefficients, which can be arbitrarily reduced, can vanish, or can even change sign, depending on the shaking parameter. It is therefore necessary to account for higher-order hopping terms, which are renormalized differently by the shaking, and introduce anisotropy into the problem. We show that the competition between these different hopping terms leads to finite-momentum condensates, with a momentum that may be tuned via the strength of the shaking. We calculate the boundaries between the Mott-insulator and the different superfluid phases, and present the time-of-flight images expected to be observed experimentally. Our results open up new possibilities for the realization of bosonic analogs of the FFLO phase describing inhomogeneous superconductivity.Comment: 7 pages, 7 figure

Beneficial role of exercise in the modulation of mdx muscle plastic remodeling and oxidative stress

Duchenne muscular dystrophy (DMD) is an X-linked recessive progressive lethal disorder caused by the lack of dystrophin, which determines myofibers mechanical instability, oxidative stress, inflammation, and susceptibility to contraction-induced injuries. Unfortunately, at present, there is no efficient therapy for DMD. Beyond several promising gene-and stem cells-based strategies under investigation, physical activity may represent a valid noninvasive therapeutic approach to slow down the progression of the pathology. However, ethical issues, the limited number of studies in humans and the lack of consistency of the investigated training interventions generate loss of consensus regarding their efficacy, leaving exercise prescription still questionable. By an accurate analysis of data about the effects of different protocol of exercise on muscles of mdx mice, the most widely-used pre-clinical model for DMD research, we found that low intensity exercise, especially in the form of low speed treadmill running, likely represents the most suitable exercise modality associated to beneficial effects on mdx muscle. This protocol of training reduces muscle oxidative stress, inflammation, and fibrosis process, and enhances muscle functionality, muscle regeneration, and hypertrophy. These conclusions can guide the design of appropriate studies on human, thereby providing new insights to translational therapeutic application of exercise to DMD patients

A Concerted Investigation For Metal/Semiconductor Nanointerface : Interlayer Charge Transfer At Ag/TiO2

In the field of hybrid materials, suitably designed nanoheterojunctions enhance synergistic functionalities and allow to obtain \u201cbrave new materials\u201d with physicochemical properties that are not simply the addition of the precursors\u2019 ones, but are completely new, different, and sometimes unexpected. For these reasons, the use of them has paved the way toward promising applications in many fields, such as electrocatalysis, photocatalysis, electroanalysis, and environmental chemistry, impacting on the everyday life [1]. However, research on such systems is most often dominated by trial and error procedures, while a deep atomistic understanding of the phenomena inside the junction region driving appropriate design of the final device is missing. Here, a concerted theoretical and electrochemical investigation is proposed to gain insights into the important class of heterojunctions made by metal-semiconductor interfaces. The presented case of study is the silver/anatase hybrid nanocomposite, a very promising material for advanced sensing applications [2]. Considering that in most cases titania semiconductors are useless in electroanalysis and silver is subject to fouling and oxidation/passivation, such broad outcomes were totally unexpected. Specifically, Ag/TiO2 interfase provided the first photorenewable sensor device, pushing the limits in terms of accuracy, sensitivity, detection limits, and photoactivity [3]. Despite the ongoing research, a quantitative and comprehensive understanding of the physics behind this nanocomposite is still missing, thus preventing its full exploitation and the extension of the same paradigm to other systems and devices. In particular, cyclic voltammetry and electrochemical impedance spectroscopy are used in combination with periodic plane-wave DFT calculations, giving comparable qualitative, but also quantitative results. We measure the exceptional electrochemical virtues of the Ag/TiO2 junction in terms of current densities and reproducibility, providing their explanation at the atomic-scale level and demonstrating how and why silver acts as a positive electrode [4]. We theoretically estimate the overall amount of electron transfer toward the semiconductor side of the interface at equilibrium and suitably designed electrochemical experiments strictly agree with the theoretical charge transfer estimates. Moreover, photoelectrochemical measurements and theoretical predictions show the unique permanent charge separation occurring in the device, possible because of the synergy of Ag and TiO2, which exploits in a favorable band alignment, in a smaller electron\u2013hole recombination rate and in a reduced carrier mobility when electrons cross the metal\u2013semiconductor interface. Finally, the hybrid material is proven to be extremely robust against aging, showing complete regeneration, even after one year [4]. [1] A.V. Emeline, V.N. Kuznetsov, V.K. Ryabchuk, N. Serpone, Environ. Sci. Pollut. Res. 19 (2012) 3666\u20133675. [2] G. Soliveri, V. Pifferi, G. Panzarasa, S. Ardizzone, G. Cappelletti, D. Meroni, K. Sparnacci, L. Falciola, Analyst 140 (2015) 1486\u20131494. [3] V. Pifferi, G. Soliveri, G. Panzarasa, G. Cappelletti, D. Meroni, L. Falciola, Anal. Bioanal. Chem. 408 (2016) 7339\u20137349. [4] G. Di Liberto, V. Pifferi, L. Lo Presti, M. Ceotto, and L. Falciola, J. Phys. Chem. Lett. 8 (2017) 5372\u20135377

A Concerted Electrochemical and Theoretical Investigation of the Ag/TiO2 nano-heterojunction

Suitably designed nano-heterojunctions are able to enhance synergistic functionalities of different materials yielding to \u201cbrave new systems\u201d with innovative and sometimes unexpected physicochemical properties [1]. However, the complete understanding of these devices has to be deeply studied. In this work, a concerted theoretical and electrochemical investigation is proposed to gain insights into a metal-semiconductor interface, namely that created by the silver/anatase hybrid nanocomposite, a promising material for advanced sensing applications [2]. In particular, it provided the first photorenewable and anti-fouling sensor device, enhancing the analytical limits in terms of accuracy, sensitivity, detection limits, and photoactivity [3]. Furthermore, the hybrid material is proven to be extremely robust against aging, showing complete regeneration, also after one-year storage. The electrochemical/electroanalytical virtues of the Ag/TiO2 junction were evaluated in terms of current densities and reproducibility, providing their explanation at the atomic-scale level and demonstrating how and why the final device can act as silver-cation positive electrode [4]. Moreover, Cyclic Voltammetry and Electrochemical Impedance Spectroscopy were used in combination with periodic plane-wave DFT calculations, giving comparable qualitative but also quantitative results. In particular, we theoretically estimated the overall amount of electron transfer toward the semiconductor side of the interface at equilibrium and suitably designed electrochemical experiments, which strictly agree with the theoretical charge transfer estimates. Moreover, photoelectrochemical measurements and theoretical predictions show the unique permanent charge separation occurring in the device [4]. [1] A.V. Emeline, V.N. Kuznetsov, V.K. Ryabchuk, N. Serpone, Environ. Sci. Pollut. Res., 2012, 19, 3666\u20133675. [2] G. Soliveri, V. Pifferi, G. Panzarasa, S. Ardizzone, G. Cappelletti, D. Meroni, K. Sparnacci, L. Falciola, Analyst, 2015, 140, 1486\u20131494. [3] V. Pifferi, G. Soliveri, G. Panzarasa, G. Cappelletti, D. Meroni, L. Falciola, Anal. Bioanal. Chem., 2016, 408, 7339\u20137349. [4] G. Di Liberto, V. Pifferi, L. Lo Presti, M. Ceotto, L. Falciola, J. Phys. Chem. Lett., 2017, 8, 5372\u20135377

Constraints on mantle source and interactions from He-Sr isotope variation in Italian Plio-Quaternary volcanism

Helium isotope ratios of olivine and pyroxene phenocrysts from Plio-Quaternary volcanic rocks from Southern Italy (seven Eolian Islands, Mt. Vulture, Etna, Ustica, Pantelleria) range from 2.3 to 7.1 Ra. Importantly the phenocryst 3He/4He correlate well with whole rock Sr isotopic composition (0.70309-0.70711) reflecting the mixing of two sources. A significant contribution of He from crustal contamination is recorded only occasionally (e.g., pyroxenes from Vulcano). When merged with data from the Roman Comagmatic Province, a remarkably strong near-linear He-Sr isotope correlation is apparent. The general northward decrease in 3He/4He corresponds to an increase in 87Sr/86Sr (and decrease in 143Nd/144Nd and 206Pb/204Pb) that is due to increasing metasomatic enrichment of the mantle wedge via subduction of the Ionian-Adriatic plate. Calculations based on the ingrowth of 4He in the wedge and on the 4He content of the subducting crust show that mechanisms of enrichment in radiogenic He are effective only if the wedge is strongly depleted in He relative to best estimates of the depleted mantle. This can be accommodated if the process of metasomatism by the subduction fluids depletes the mantle wedge. The 3He/4He of Pantelleria, Etna, Iblei, Ustica, Alicudi and Filicudi basalts (7.0 ± 0.6 Ra) define the mantle composition least affected by subduction-related metasomatism. Although these volcanoes are from a variety of tectonic regimes (subduction-related, intraplate, rifting) their similarities suggest a common origin of geochemical features. Their characteristics are consistent with a HIMU-type mantle that is either younger than the Cook-Austral island end-member, or has a lower 238U/204Pb

FGF-2/FGFR1 neurotrophic system expression level and its basal activation do not account for the age-dependent decline of precursor cell proliferation in the subventricular zone of rat brain.

It is largely accepted that neurogenesis in the adult brain decreases with age and reduced levels of local neurotrophic support is speculated to be a contributing factor. Among neurotrophic factors involved on neurogenesis, we focused our attention on the neurotrophic system fibroblast growth factor-2 (FGF-2) and its receptor FGFR1, a potent modulator of precursor cell proliferation. In the present work, we aimed to analyse if potential age-dependent changes of the FGF-2/FGFR1 neurotrophic system may give account for the age-dependent decline of precursor cell proliferation in the neurogenic region of the subventricular zone (SVZ) in the rat brain. Using in situ hybridization and western blotting procedures we examined FGF-2 and FGFR1 expression levels in the SVZ of 20-month-old rats as compared to young adult 3-month-old rats. The results showed that during aging the FGF-2 and its receptor expression levels, both as mRNA and protein, were unchanged in the SVZ. The levels of phosphorylated FGFR1 form did not show significant variations suggesting that also the level of receptor activation does not change during aging. No changes were also observed in the phosphorylation of two FGFR1 related proteins involved in intracellular signaling, the canonical extracellular signal-regulated kinase Erk1/2 and the phospholipase-C\u3b31. Additionally, we could show that also the proliferation rate of stem cells does not change during aging. Taken together, our results show that FGF-2/FGFR1 neurotrophic system expression level and its basal activation do not account for the age-dependent decline of precursor cell proliferation in the rat brain

Adipose Stromal/Stem Cell-Derived Extracellular Vesicles: Potential Next-Generation Anti-Obesity Agents

Over the last decade, several compounds have been identified for the treatment of obesity. However, due to the complexity of the disease, many pharmacological interventions have raised concerns about their efficacy and safety. Therefore, it is important to discover new factors involved in the induction/progression of obesity. Adipose stromal/stem cells (ASCs), which are mostly isolated from subcutaneous adipose tissue, are the primary cells contributing to the expansion of fat mass. Like other cells, ASCs release nanoparticles known as extracellular vesicles (EVs), which are being actively studied for their potential applications in a variety of diseases. Here, we focused on the importance of the con-tribution of ASC-derived EVs in the regulation of metabolic processes. In addition, we outlined the advantages/disadvantages of the use of EVs as potential next-generation anti-obesity agents

Reinforcement Learning for Variable Selection in a Branch and Bound Algorithm

Mixed integer linear programs are commonly solved by Branch and Bound algorithms. A key factor of the efficiency of the most successful commercial solvers is their fine-tuned heuristics. In this paper, we leverage patterns in real-world instances to learn from scratch a new branching strategy optimised for a given problem and compare it with a commercial solver. We propose FMSTS, a novel Reinforcement Learning approach specifically designed for this task. The strength of our method lies in the consistency between a local value function and a global metric of interest. In addition, we provide insights for adapting known RL techniques to the Branch and Bound setting, and present a new neural network architecture inspired from the literature. To our knowledge, it is the first time Reinforcement Learning has been used to fully optimise the branching strategy. Computational experiments show that our method is appropriate and able to generalise well to new instances

Recent Advances on the Innate Immune Response to Coxiella burnetii.

Coxiella burnetii is an obligate intracellular Gram-negative bacterium and the causative agent of a worldwide zoonosis known as Q fever. The pathogen invades monocytes and macrophages, replicating within acidic phagolysosomes and evading host defenses through different immune evasion strategies that are mainly associated with the structure of its lipopolysaccharide. The main transmission routes are aerosols and ingestion of fomites from infected animals. The innate immune system provides the first host defense against the microorganism, and it is crucial to direct the infection towards a self-limiting respiratory disease or the chronic form. This review reports the advances in understanding the mechanisms of innate immunity acting during C. burnetii infection and the strategies that pathogen put in place to infect the host cells and to modify the expression of specific host cell genes in order to subvert cellular processes. The mechanisms through which different cell types with different genetic backgrounds are differently susceptible to C. burnetii intracellular growth are discussed. The subsets of cytokines induced following C. burnetii infection as well as the pathogen influence on an inflammasome-mediated response are also described. Finally, we discuss the use of animal experimental systems for studying the innate immune response against C. burnetii and discovering novel methods for prevention and treatment of disease in humans and livestock

Impact of “Golden” tomato juice on cognitive alterations in metabolic syndrome: Insights into behavioural and biochemical changes in a high-fat diet rat model

“Golden” tomato (GT) plays a protective role in metabolic dysfunction induced by High-Fat Diet (HFD). Our aim is to characterize the phytonutrient composition of the juice and explore the influence of GT, orally administered for one month, on cognitive impairment associated with Metabolic Syndrome (MetS) in male rats. We investigated reactivity, stress response and memory, together with brain neurotrophic/inflammatory signaling. Our data showed that HFD-induced functional modifications were ameliorated by GT nutritional supplementation. In particular, the behavioural reactivity improved in HFD/GT rats, that also showed a better performance in tests measuring anxiety and anhedonia. Furthermore, GT consumption rescued the declarative memory impairment. Lastly, GT supplementation counteracted HFD-induced brain alterations in PI3K\Akt and MAPK/ERK signalling pathways. In conclusion, this study provides evidence of the importance of food supplementation with GT in the protection from neuroinflammation and cognitive alterations associated with MetS