The evolution of a slow electrostatic shock into a plasma shock mediated by electrostatic turbulence

The collision of two plasma clouds at a speed that exceeds the ion acoustic speed can result in the formation of shocks. This phenomenon is observed not only in astrophysical scenarios such as the propagation of supernova remnant (SNR) blast shells into the interstellar medium, but also in laboratory-based laser-plasma experiments. These experiments and supporting simulations are thus seen as an attractive platform for the small-scale reproduction and study of astrophysical shocks in the laboratory. We model two plasma clouds, which consist of electrons and ions, with a 2D PIC simulation. The ion temperatures of both clouds differ by a factor of 10. Both clouds collide at a speed, which is realistic for laboratory studies and for SNR shocks in their late evolution phase like that of RCW86. A magnetic field, which is orthogonal to the simulation plane, has a strength that is comparable to that at SNR shocks. A forward shock forms between the overlap layer of both plasma clouds and the cloud with the cooler ions. A large-amplitude ion acoustic wave is observed between the overlap layer and the cloud with the hotter ions. It does not steepen into a reverse shock, because its speed is below the ion acoustic speed. A gradient of the magnetic field amplitude builds up close to the forward shock as it compresses the magnetic field. This gradient gives rise to an electron drift that is fast enough to trigger an instability. Electrostatic ion acoustic wave turbulence develops ahead of the shock. It widens its transition layer and thermalizes the ions, but the forward shock remains intact.Comment: Accepted for publication in the New Journal of Physic

Novel voltage compressor circuit by transmission lines

0034-674

NEW TRENDS IN THE BIOACTIVE COMPOUNDS OF MILK: A REVIEW OF THE FUNCTIONAL ACTIVITIES AND PROCESSING EFFECTS

Milk has a complex highly variable nutritional com-position based on the different species and animal breeds, together with the strategy and management of the animal feed. It is the first food consumed by chil-dren, exclusively for the initial months because it contains all the nutrients necessary for body growth and the development of cognitive functions. Consid-ering the Mediterranean diet, cow and goat milk is consumed fresh or used for the production of dairy products, while sheep and buffalo milk is used exclu-sively for cheese production. In developing countries, sheep milk or milk from particular animal species such as the yak is also used for fresh consumption and is a low-cost food source for consumers. Milk is the only raw food with a complete profile of all nutri-ents, from proteins to fats, carbohydrates, water, min-erals, and vitamins. Several bioactive compounds are present in milk or originate during protein digestion and fat fraction. Thus, milk can be defined as a func-tional food because it adapts to the definition "any food or food ingredient that can provide a health ben-efit over the traditional nutrients it contains"

Laser-driven muon production for material inspection and imaging

We numerically show that laser-wakefield accelerated electron beams obtained using a PetaWatt-scale laser system can produce high-flux sources of relativistic muons that are suitable for radiographic applications. Scalings of muon energy and flux with the properties of the wakefield electron beams are presented. Applying these results to the expected performance of the 10-PW class laser at the Extreme Light Infrastructure Nuclear Physics (ELI-NP) demonstrates that ultra-high power laser facilities currently in the commissioning phase can generate ultra-relativistic muon beams with more than 104 muons per shot reaching the detector plane. Simple magnetic beamlines are shown to be effective in separating the muons from noise, allowing for their detection using, for example, silicon-based detectors. It is shown that a laser facility like the one at ELI-NP can produce high-fidelity and spatially resolved muon radiographs of enclosed strategically sensitive materials in a matter of minutes

Experimental Observation of the Thin-Shell Instability in a Collision-less Plasma

We report on the experimental observation of the instability of a plasma shell, which formed during the expansion of a laser-ablated plasma into a rarefied ambient medium. By means of a proton radiography technique, the evolution of the instability is temporally and spatially resolved on a timescale much shorter than the hydrodynamic one. The density of the thin shell exceeds that of the surrounding plasma, which lets electrons diffuse outward. An ambipolar electric field grows on both sides of the thin shell that is antiparallel to the density gradient. Ripples in the thin shell result in a spatially varying balance between the thermal pressure force mediated by this field and the ram pressure force that is exerted on it by the inflowing plasma. This mismatch amplifies the ripples by the same mechanism that drives the hydrodynamic nonlinear thin-shell instability (NTSI). Our results thus constitute the first experimental verification that the NTSI can develop in colliding flows.Funding agencies: EPSRC [EP/I031766/1, EP/K022415/1, EP/I029206/1, SFB-TR18, GRK1203, ENE2013-45661-C2-1-P, PEII-2014-008-P]; Vetenskapsradet [Dnr 2010-4063]; Triangle de la Physique RTRA network (ULIMAC)</p

First observation of quantum interference in the process phi -> KS KL ->pi+pi-pi+pi-: a test of quantum mechanics and CPT symmetry

We present the first observation of quantum interference in the process phi -> KS KL ->pi+pi-pi+pi-. This analysis is based on data collected with the KLOE detector at the e^+e^- collider DAFNE in 2001--2002 for an integrated luminosity of about 380pb^-1. Fits to the distribution of Delta t, the difference between the two kaon decay times, allow tests of the validity of quantum mechanics and CPT symmetry. No deviations from the expectations of quantum mechanics and CPT symmetry have been observed. New or improved limits on various decoherence and CPT violation parameters have been obtainedComment: submitted to Physics Letter B one number changed old:gamma=(1.1+2.9-2.4)10^-21 GeV new:(1.3+2.8-2.4)10^-21GeV corrected typo

Study of the a_0(980) meson via the radiative decay phi->eta pi^0 gamma with the KLOE detector

We have studied the phi->a_0(980) gamma process with the KLOE detector at the Frascati phi-factory DAPhNE by detecting the phi->eta pi^0 gamma decays in the final states with eta->gamma gamma and eta->pi^+ pi^- pi^0. We have measured the branching ratios for both final states: Br(phi->eta pi^0 gamma)=(7.01 +/- 0.10 +/- 0.20)x10^-5 and (7.12 +/- 0.13 +/- 0.22)x10^-5 respectively. We have also extracted the a_0(980) mass and its couplings to eta pi^0, K^+ K^-, and to the phi meson from the fit of the eta pi^0 invariant mass distributions using different phenomenological models.Comment: 17 pages, 6 figures, submitted to Physics Letters B. Corrected typos in eq.

Similarities and differences between younger and older disease onset patients with newly diagnosed systemic lupus erythematosus

Objectives: Several studies show that age at onset has an impact on the clinical-serological presentation, comorbidities and disease course of patients with systemic lupus erythematosus (SLE). We evaluated whether, in patients with recent onset SLE, the age at onset correlates with clinical-serological manifestations and with comorbidities. Methods: We analysed 171 patients with a SLE diagnosis obtained within 12 months of diagnosis enrolled in the Early Lupus project. Based on the age of onset of the first disease symptom, they were stratified into 2 groups: early onset (18-45 years) and late onset (&gt;45 years). The analysis was replicated by stratifying patients based on age at diagnosis (fulfillment of ACR classification criteria). Each comparison was made at baseline and at 36 months of follow-up. Results: Baseline: patients with late onset displayed comorbidities (hypertension, dyslipidemia and osteoporosis) more frequently than early onset group. 11.4% of late onset patients had a malignancy in medical history, not recorded in the early onset cohort. The two groups differed neither in organ involvement (domain BILAG) nor in disease activity (ECLAM). Patients with early onset showed a disease with signs of higher serologic activity (higher frequency of anti-dsDNA positivity and lower mean C3 and C4 levels) and had malar rash more frequently than the late onset group (36.2% vs. 18.2%, p=0.042). Similar results were obtained by stratifying patients by age of diagnosis (18-45 years and &gt;45 years), except for the higher frequency of discoid rash in the group with age at diagnosis &gt;45 years (18% vs. 6.6%, p=0.045). 36 months: the 2 groups of patients independently of the stratification applied did not differ in the accumulation of damage, but showed a different pattern of 8 organ involvement. Musculoskeletal involvement was more frequent both in the late onset group (18.6% vs. 7.3%, p=0.043) and in the group with age at diagnosis &gt;45 years (20.4% vs. 5.9%, p=0.009) compared to their counterparts, while renal involvement was more frequent in the group with age at diagnosis 18-45 years (21.4% vs. 6.1%, p=0.03).A sub analysis at 36 months on patients without hypertension and osteoporosis at enrollment showed that patients with older age at onset had a higher frequency of these comorbidities, compared to their counterparts. Conclusions: In our cohort, younger disease SLE onset seems to correlate with a more active immunological profile, while late onset with a higher incidence of comorbidities