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We report on the observation and coherent excitation of atoms on the narrow inner-shell orbital transition, connecting the erbium ground state $[\mathrm{Xe}] 4f^{12} (^3\text{H}_6)6s^{2}$ to the excited state $[\mathrm{Xe}] 4f^{11}(^4\text{I}_{15/2})^05d (^5\text{D}_{3/2}) 6s^{2} (15/2,3/2)^0_7$. This transition corresponds to a wavelength of 1299 nm and is optically closed. We perform high-resolution spectroscopy to extract the $g_J$-factor of the $1299$-nm state and to determine the frequency shift for four bosonic isotopes. We further demonstrate coherent control of the atomic state and extract a lifetime of 178(19) ms which corresponds to a linewidth of 0.9(1) Hz. The experimental findings are in good agreement with our semi-empirical model. In addition, we present theoretical calculations of the atomic polarizability, revealing several different magic-wavelength conditions. Finally, we make use of the vectorial polarizability and confirm a possible magic wavelength at 532 nm., 14 pages, 6 figures

A supersolid is a counterintuitive phase of matter that combines the global phase coherence of a superfluid with a crystal-like self-modulation in space. Recently, such states have been experimentally realized using dipolar quantum gases. Here we investigate the response of a dipolar supersolid to an interaction quench that shatters the global phase coherence. We identify a parameter regime in which this out-of-equilibrium state rephases, indicating superfluid flow across the sample as well as an efficient dissipation mechanism. We find a crossover to a regime where the tendency to rephase gradually decreases until the system relaxes into an incoherent droplet array. Although a dipolar supersolid is, by its nature, ‘soft’, we capture the essential behaviour of the de- and rephasing process within a rigid Josephson junction array model. Yet, both experiment and simulation indicate that the interaction quench causes substantial collective mode excitations that connect to phonons in solids and affect the phase dynamics. A supersolid is a phase of matter featuring both crystalline order as a solid and global phase coherence as a superfluid. Now an experiment shows how this global phase coherence can be established across the system in a non-equilibrium process.

We measure the excitation spectrum of a stable dipolar Bose--Einstein condensate over a wide momentum-range via Bragg spectroscopy. We precisely control the relative strength, $\epsilon_{\rm dd}$, of the dipolar to the contact interactions and observe that the spectrum increasingly deviates from the linear phononic behavior for increasing $\epsilon_{\rm dd}$. Reaching the dipolar dominated regime $\epsilon_{\rm dd}>1$, we observe the emergence of a roton minimum in the spectrum and its softening towards instability. We characterize how the excitation energy and the strength of the density-density correlations at the roton momentum vary with $\epsilon_{\rm dd}$. Our findings are in excellent agreement with numerical calculations based on mean-field Bogoliubov theory. When including beyond-mean-field corrections, in the form of a Lee-Huang-Yang potential, we observe a quantitative deviation from the experiment, questioning the validity of such a description in the roton regime., Comment: 11 pages, 8 figures

We study the spectrum of elementary excitations of a dipolar Bose gas in a three-dimensional anisotropic trap across the superfluid-supersolid phase transition. Theoretically, we show that, when entering the supersolid phase, two distinct excitation branches appear, respectively associated with dominantly crystal and superfluid excitations. These results confirm infinite-system predictions, showing that finite-size effects play only a small qualitative role, and connect the two branches to the simultaneous occurrence of crystal and superfluid orders. Experimentally, we probe compressional excitations in an Er quantum gas across the phase diagram. While in the Bose-Einstein condensate regime the system exhibits an ordinary quadrupole oscillation, in the supersolid regime we observe a striking two-frequency response of the system, related to the two spontaneously broken symmetries., 9 pages, 6 figures

We realize a two-component dipolar Fermi gas with tunable interactions, using erbium atoms. Employing a lattice-protection technique, we selectively prepare deeply degenerate mixtures of the two lowest spin states and perform high-resolution Feshbach spectroscopy in an optical dipole trap. We identify a comparatively broad Feshbach resonance and map the interspin scattering length in its vicinity. The Fermi mixture shows a remarkable collisional stability in the strongly interacting regime, providing a first step towards studies of superfluid pairing, crossing from Cooper pairs to bound molecules, in presence of dipole-dipole interactions., Comment: 12 pages, 9 figures, including supplemental material

A peculiar infrared ring-like structure was discovered by {\em Spitzer} around the strongly magnetised neutron star SGR 1900$+$14. This infrared structure was suggested to be due to a dust-free cavity, produced by the SGR Giant Flare occurred in 1998, and kept illuminated by surrounding stars. Using a 3D dust radiative transfer code, we aimed at reproducing the emission morphology and the integrated emission flux of this structure assuming different spatial distributions and densities for the dust, and different positions for the illuminating stars. We found that a dust-free ellipsoidal cavity can reproduce the shape, flux, and spectrum of the ring-like infrared emission, provided that the illuminating stars are inside the cavity and that the interstellar medium has high gas density ($n_H\sim$1000 cm$^{-3}$). We further constrain the emitting region to have a sharp inner boundary and to be significantly extended in the radial direction, possibly even just a cavity in a smooth molecular cloud. We discuss possible scenarios for the formation of the dustless cavity and the particular geometry that allows it to be IR-bright., 13 pages, 8 figures, accepted for publication in The Astrophysical Journal

Denosumab has been proven to reduce fracture risk in breast cancer (BC) women under aromatase inhibitors (AIs). Quantitative ultrasound (QUS) provides information on the structure and elastic properties of bone. Our aim was to assess bone health by phalangeal QUS and by dual-energy X-ray absorptiometry (DXA), and to evaluate bone turnover in AIs-treated BC women receiving denosumab. 35 Postmenopausal BC women on AIs were recruited (mean age 61.2 ± 4.5 years) and treated with denosumab 60 mg administered subcutaneously every 6 months. Phalangeal QUS parameters [Amplitude Dependent Speed of Sound (AD-SoS), Ultrasound Bone Profile Index (UBPI), Bone Transmission Time (BTT)] and DXA at lumbar spine and femoral neck were performed. Serum C-telopeptide of type 1 collagen (CTX) and bone-specific alkaline phosphatase (BSAP) were also measured. The main outcomes were compared with a control group not receiving denosumab (n = 39). In patients treated with denosumab, differently from controls, QUS and DXA measurements improved after 24 months, and a reduction of CTX and BSAP was detected at 12 and 24 months in comparison to baseline (P

Branchial abnormalities occur when there is disturbance in the maturation of the branchial apparatus during fetal development. Branchial anomalies are congenital lesions usually present in childhood, even if they can be diagnosed later for enlargement or infection. A correct diagnosis will lead to proper management: complete surgical excision is the treatment of choice. The purpose of this article is to present clinical features, diagnostic methods and surgical treatment of branchial anomalies in childhood, based on a series of 50 patients. We conducted a retrospective analysis of a total of 50 pediatric patients operated from June 2005 to June 2014 for the presence of branchial cleft anomalies. 27 cases (54 %) presented a second branchial cleft fistula and 11 cases (22 %) a second branchial cleft cyst and one case (2 %) presented both cyst and sinus of the second branchial cleft; four cases (8 %) presented first branchial cleft cyst whereas four cases (8 %) a first branchial cleft sinus and two cases (4 %) a first branchial cleft fistula; one case (2 %) presented a piriform sinus fistula (third branchial cleft). None of our patients presented anomalies of the fourth branchial cleft. All patients underwent surgical treatment and lesions have been removed by excision or fistulectomy. No post-surgical complication occurred. The rate of recurrence was 4 %. Pre-operative diagnosis supplies important information to the surgeon for a proper therapy: a complete excision of the lesion without inflammatory signs is essential to avoid re-intervention and to achieve a good outcome.

The status of advancement of the VIRGO Project is presented: the first-generation results from the Pisa seismic noise super attenuator give an upper limit to the noise transfer function of 2 × 10 −8 at 10 Hz. The upper limit to the absolute noise of the 400 kg test mass at 10 Hz has been measured to be 1.5 × 10 −13 m/√Hz. The scheme and the related problems of the VIRGO interferometer, which is supposed to work down to 10 Hz, are also presented. At the 3rd Pisa Meeting in 1986 we presented the idea of what could be a very efficient seismic noise reduction system able to give a sensitivity h ∼ 10 −25 at 10 Hz, in a 3 km interferometer for 1 year integration time. Now we have two new facts to present: the first is that the attenuation has been built, is working in Pisa, and shows remarkable characteristics. The second is the Italian-French interferometer VIRGO [1,2], a 3 km long antenna for low and high frequency (10–1000 Hz) gravitational wave (GW) detection. These two items will be presented in this article.

An analytical model for rock deformation and fracturing processes due to nonlinear waves of temperature and pressure and evolving with particularly large velocities in a fluid-saturated rock over a hyperthermal aquifer is here discussed. As in classical studies by Rice and Cleary [1976], McTigue [1986], and also Bonafede [1991] and Natale and Salusti [1996], the upper fluid-saturated matrix is considered homogeneous, thermoelastic, and isotropic in a one-dimensional formulation. As regards the nonlinear wave generation mechanism, at the boundary between the two horizons the hot fluid from below is forced upward by a pressure gradient, thus giving rise to strong pressure and temperature perturbations. In such a context, in order to schematize wave-induced rock deformation and fracturing processes we assume a continuous temperature and pressure dependence of model parameters such as fluid diffusivity and thermal expansivity of the rock and fluid. The solution we obtain is a strong shock wave corresponding to nonlinear fluid migration mechanisms, in turn enhanced by the flow through the induced fractures in the overlying rock. It has to be stressed that once such a process starts off, it may be amplified and also may produce rather catastrophic behavior in the natural system. This model essentially provides a theoretical tool for interpreting such geophysical effects, in particular for volcanic complexes such as the Rabaul caldera, Long Valley caldera, Campi Flegrei, the island of Vulcano, or similar kinds of geological system.

—This work is a further development of the modern thermo-poro-elasticity theory which has recently been applied to understand how fluid-rock coupling dynamics related to unrest episodes in volcanic domains can both determine, and occur with, ground deformation and rock fracturing processes. In particular by reformulating the energy equation, one of the two nonlinear heat-like equations upon which the thermo-poroelasticity theory is based, it is shown here how fluid thermal expansivity may influence fluid migration during its movement through subsurface volcanic porous-per meable horizons. With these new considerations it is found that a recent theory in which fluid-rock coupling dynamics is interpreted in terms of thermal and mechanical solitary shock wave propagation remains valid. However, the natural time scale of the propagating wave is reduced and consequently Darcy’s velocity is increased as a result of fluid thermal expansivity.

Neurodegenerative diseases may extend outside the central nervous system (CNS) and involve the gastrointestinal (GI) tract. The gut would appear to be a pathological marker for neurodegeneration, as well as a site for studying the pathophysiology of neurodegeneration. In fact, both in the ENS and CNS, misfolded proteins are likely to initiate a process of neurodegeneration. For example, the very same protein aggregates can be detected both in the ENS and CNS. In both systems, misfolded proteins are likely to share common cell-to-cell diffusion mechanisms, which may occur through a parallel prion-like diffusion process. Independently from the enteric or central origin, misfolded proteins may proceed along the following steps, they: (i) form aggregates; (ii) are expressed on plasma membrane; (iii) are secreted extracellularly; (iv) are glycated to form advanced glycation end-products (AGEs); (v) are internalized through specific receptors placed on neighboring cells (RAGEs); (vi) are cleared by autophagy; and (vii) are neurotoxic. These features are common for a-synuclein (in Parkinson's disease and other synucleinopathies), β-amyloid and tau (in degenerative dementia), SOD-1 and TDP43 (in amyotrophic lateral sclerosis), and PrPsc (in prion diseases). While in some diseases these features are common to both ENS and CNS, in others this remains a working hypothesis.This review analyzes GI alterations from a pathological perspective to assess whether the enteric nervous system (ENS) mirrors the neuropathology described in the CNS. We discuss the potential mechanisms that lead to the onset and spread of neurodegeneration within the gut, from the gut to the brain, and vice versa.

We present new infrared images of the prototype of galaxy compact groups, Stephan’s Quintet (SQ), taken with Spitzer/MIPS at 24, 70 and 160 μm, and compare these with existing images at X‐ray, UV/optical, radio wavelengths as well as with archival Spitzer/IRAC imaging at 8 μm. The new images reveal an extended (on scales of up to ca. 70 kpc) component of FIR emission which is roughly correlated with diffuse soft X‐ray emission arising from the so‐called SHOCK and HALO regions. A further interesting aspect of this study is the displacement of the main star formation sites from the central galaxy disks to the peripheries of the galaxies or to the intergalactic medium (IGM).

The present paper proposes a new flexible and effective evaluation tool based on genetic algorithms to test the robustness of digital image watermarking techniques. Given a set of possible attacks, the method finds the best possible un-watermarked image in terms of Weighted Peak Signal to Noise Ratio (WPSNR). In fact, it implements a stochastic search of the optimal parameters to be assigned to each processing operation in order to find the combined attack that removes the watermark while producing the smallest possible degradation of the image in terms of human perception. As a result, the proposed method makes it possible to assess the overall performance of a watermarking scheme, and to have an immediate feedback on its robustness to different attacks. A set of tests is presented, referring to the application of the tool to two known watermarking approaches.

In this article we present a board developed to test algorithms for real-time digital audio signals. Some algorithms have been implemented for the Acoustic Echo Cancellation (AEC). The proposed system can be used during hands free audio conversations in a full-duplex communication. Moreover, the system is able to operate both in personal mode (one to one) and in conference mode (many to many).

Ring patterns of concentric 2pi solitons in molecular orientation form in freely suspended chiral smectic-C films in response to an in-plane rotating electric field. We present measurements of the driven dynamics of ring formation under conditions of synchronous winding and of the zero-field relaxation of ring patterns, and propose a simple model which enables their quantitative description in low polarization DOBAMBC. In smectic-C*A TFMHPOBC we observe an odd-even layer number effect, with odd layer number films exhibiting order of magnitude slower relaxation rates than even layer films. We show that this rate difference is due to a much larger spontaneous polarization in odd layer number films.

The protective effects of the proton pump inhibitor lansoprazole on gastric mucosal damage induced by ethanol-HCl or hemorrhagic shock were investigated in the present study. The morphometric analysis of gastric histological sections revealed that lansoprazole dose-dependently reduced mucosal injury evoked by ethanol-HCl (ED50 = 24.3 micromol/kg) or hemorrhagic shock (ED50 = 38.9 micromol/kg), these effects being associated with marked increments of Alcian blue recovery from gastric bound mucus (ED50 = 31.4 micromol/kg and 27.6 micromol/kg, respectively). In addition, lansoprazole inhibited gastric acid secretion from pylorus-ligated rats (ED50 = 9.8 micromol/kg). Further experiments, performed on rats with ethanol-HCl-induced gastric injury, indicated that the protective effects of lansoprazole were not modified by L-365,260, suramin, N(G)-nitro-L-arginine, or systemic ablation of capsaicin-sensitive sensory nerves, whereas they were partly blocked by indomethacin and fully prevented by N-ethyl-maleimide. In addition, lansoprazole did not modify somatostatin concentrations in gastric mucosa. The present results provide evidence that lansoprazole prevents the necrotic damage of gastric mucosa induced by ethanol-HCl or hemorrhagic shock. According to the rank order of ED50 values, these effects appear to depend mainly on the enhancement of the gastric mucus barrier rather than on the reduction of acid secretion. It is also proposed that an increased production of prostaglandins, as well as an increased availability of sulfhydryl compounds at level of gastric mucosa may account for the gastroprotective effects of lansoprazole.

4-Methylpyrazole (4-MP), a specific inhibitor of alcohol dehydrogenase, exerts gastroprotection of unusually long duration in rats. We tested the hypothesis that pretreatment with 4-MP might protect the human gastric mucosa against alcohol-induced acute injury. Fourteen healthy volunteers received pretreatment with either 4-MP, 15 mg/kg body weight dissolved in 50 ml of orange juice, or placebo and 2 hr later 100 ml of 40% ethanol. The endoscopic appearance of the gastric mucosa was evaluated and scored (scale 0-5) and mucosal biopsies were obtained just before pretreatment and 30 min after ethanol for histologic examination and prostaglandin E2 measurement. In the 4-MP group the mean endoscopic injury score was significantly lower than that in placebo group, in both the body and the antrum. Histologically, 4-MP significantly reduced disruption of surface epithelium and completely prevented the deep hemorrhagic mucosal lesions. In the 4-MP group no changes in gastric mucosal PGE2 levels were detected. In rats, 4-MP did not inhibit gastric acid output, whereas it markedly increased the adherent gastric mucus evaluated by the alcian blue recovery method. When lipid peroxidation was induced by carbon tetrachloride in hepatic microsomes, 4-MP caused significant inhibition of malondialdehyde generation. We conclude that 4-MP provides significant protection of the human stomach against alcohol-induced acute mucosal injury. 4-MP, besides inhibiting the conversion of alcohol to acetaldehyde, might protect the gastric mucosa by increasing adherent gastric mucus and by scavenging free radicals.

Suramin is currently used in clinical practice as antineoplastic agent because of its complex interaction with the biological activity of various growth factors involved in tumor progression. The influence exerted by suramin on gastric injury induced in rats by intraluminal injection of absolute ethanol was investigated in the present study. The morphometric analysis of gastric histological sections revealed that suramin, 18 mg/kg, administered intraperitoneally for 14 days every other day, caused a marked enhancement of ethanol-induced mucosal damage. This effect was more pronounced 1-8 hr following ethanol administration, and it was still significant after 48 hr. In suramin-treated animals the evaluation of Alcian blue recovery from gastric-bound mucus showed that the levels of adherent mucus were significantly lower than those detected in untreated rats. In addition, pretreatment with suramin did not modify basal acid secretion, but caused potentiation of acid output stimulated by pylorus ligation or electrical vagal stimulation. Overall, the present results indicate that suramin exerts a negative influence on both gastric protective and repairing mechanisms. Due to the peculiar pharmacodynamic profile of suramin, it is suggested that interference with endogenous growth factors, endowed with physiological protective activity on gastric mucosa, might account for the damage-enhancing action of this drug.

While reserpine and nicardipine pretreatment induced a more or less marked decrease in typical red-orange doxorubicin fluorescence in certain rat tissues, such as spleen, kidney and large intestine, the myocardial tissue (right atrium and left ventriculum) did not show any significant variations in nuclear doxorubicin storage. This different behaviour of cardiac tissue may be related to the well-known doxorubicin cardiotoxicity.

The investigation of ultrasonic propagation properties in liquid crystals in recent years has provided a considerable contribution to the study of these systems. In this paper most ultrasonic measurements performed to date on nematic liquid crystals are examined and presented in a systematic way, in order to provide a compact and coherent view of the current experimental situation in this field. The review of the available experimental data and their comparison with the predictions of various theories point out areas which necessitate further investigation by ultrasonic experiments.

The study of ultrasonic propagation in liquid crystals, greatly intensified in recent years, has provided a useful contribution to the knowledge we currently have about these systems. A previous paper (Part I of a two‐part series) contains a review and analysis of the ultrasonic work done on the nematic mesophase. In the present paper, most ultrasonic experimental investigations performed to date in smectic and cholesteric compounds, and some liquid‐crystalline mixtures, are presented in a systematic manner; the results are discussed and compared, whenever possible, to the predictions of several theories (outlined in the paper) for the various mesophases and the many possible phase transitions. In the course of this analysis, several areas which need further ultrasonic studies are identified; these areas are summarized in the concluding section of the paper.

Measurements of ultrasonic attenuation due to electron-lattice interaction were made on potassium wire samples with a pulse-echo or resonant-decay technique from 2.5 to 20\ifmmode^\circ\else\textdegree\fi{}K at frequencies between 200 and 400 kc/sec ($\mathrm{ql}\ensuremath{\ll}1$ region). The magnitude of the attenuation was found to be on the average 1.6 times larger than predicted by the free-electron theories on the basis of the measured values of electrical conductivity. The imperfect knowledge of the background introduced a maximum 30% error. Various reasons for the observed discrepancy are discussed, but the results may be within the limits of the approximations involved in the theories. The temperature and frequency dependence of the attenuation were found to be in good agreement with the theoretical expectations.

The purpose of these present experiences was to evaluate some metabolic parameters, which can show liver damage after end-to-side porto-caval shunt, comparing the data with "sham operated" rats. At 180th day in each group the following parameters were controlled: ALT, AST, Alkaline phosphatase, gamma GT, bilirubin, Cholesterol, albumin and ammonia blood level. The results showed a significant increase of gamma GT, APh, bilirubin and ammonia blood level in porto-caval shunt operated rats.

The aim of our research was to evaluate same coagulative parameters in the rat after end-to-side porto-caval shunt, comparing the data with "sham operated" rats. At 180th day in each group the following parameters were controlled: platelet, fibrinogen, prothrombin time, partial thromboplastin time, T.E.G. The results have shown a significant diminution in the following parameters: PLT, PT, fibrinogen, and T.E.G.

Evidence is reported for the same two-particle correlations in rapidity space in soft, high-energy (pp) collisions and (e+e-) annihilation when the leading baryons’ effects are taken into account.

The problem of detecting electrons in the 0.5–4.0 GeV energy range, in the presence of a high pion background, has been studied using a new type of electromagnetic shower detector. Its structural properties and the main parameters are given, together with the basic results in terms of energy resolution and of rejection power against pion background. The optimization of this new instrument gives a pion rejection power of ∼ 6 × 10 −4 for energy ≳ 1.2 GeV.