Bright correlated twin-beam generation and radiation shaping in high-gain parametric down-conversion with anisotropy.

Uniaxial anisotropy in nonlinear birefringent crystals limits the efficiency of nonlinear optical interactions and breaks the spatial symmetry of light generated in the parametric down-conversion (PDC) process. Therefore, this effect is usually undesirable and must be compensated for. However, high gain may be used to overcome the destructive role of anisotropy in order to generate bright two-mode correlated twin-beams. In this work, we provide a rigorous theoretical description of the spatial properties of bright squeezed light in the presence of strong anisotropy. We investigate a single crystal and a system of two crystals with an air gap (corresponding to a nonlinear SU(1,1) interferometer) and demonstrate the generation of bright correlated twin-beams in such configurations at high gain due to anisotropy. We explore the mode structure of the generated light and show how anisotropy, together with crystal spacing, can be used for radiation shaping.

Techno-economic assessment at full scale of a biogas refinery plant receiving nitrogen rich feedstock and producing renewable energy and biobased fertilisers.

Anaerobic digestion of nitrogen (N) rich substrates might be hindered when ammonia (NH3) formation reaches toxic levels for methanogenic microorganisms. One possible strategy to avoid inhibiting conditions is the removal of NH3 from digestate by stripping and scrubbing technology and by recirculating N depleted digestate back to the digester. This study aimed to i) monitor the performance (mass and energy balances) of a full scale digestate processing cascade that includes an innovative vacuum side stream NH3stripping and scrubbing system, ii) assess the production cost of ammonium sulphate (AS) solution and iii) evaluate its fertiliser quality. The use of gypsum to recover NH3 in the scrubbing unit, instead of the more common sulphuric acid, results in the generation of AS and a fertilising liming substrate. Mass and nutrient balances indicated that 57% and 7.5% of ammonium N contained in digestate was recovered in the form of a 22% AS and liming substrate, respectively. The energy balance showed that about 3.8 kWhel and 59 kWhth were necessary to recover 1 kg of N in the form of AS. Furthermore, the production cost of AS, including both capital and operational costs, resulted to be 5.8 € t-1 of digestate processed. According to the fertiliser quality assessment, this technology allows for the recovery of NH3in the form of salt solutions that can be utilised as a substitute for synthetic mineral nitrogen fertilisers.

Nonlinearity-induced localization in a periodically driven semidiscrete system.

We demonstrate that nonlinearity plays a constructive role in supporting the robustness of dynamical localization in a system which is discrete in one dimension and continuous in the orthogonal one. In the linear regime, time-periodic modulation of the gradient strength along the discrete axis leads to the usual rapid spread of an initially confined wave packet. Addition of the cubic nonlinearity makes the dynamics drastically different, inducing robust localization of moving wave packets. Similar nonlinearity-induced effects are also produced in the presence of a combination of static and oscillating linear potentials. The predicted dynamical localization in the nonlinear medium can be realized in photonic lattices and Bose-Einstein condensates.

Signatures of transient Wannier-Stark localization in bulk gallium arsenide.

Many properties of solids result from the fact that in a periodic crystal structure, electronic wave functions are delocalized over many lattice sites. Electrons should become increasingly localized when a strong electric field is applied. So far, this Wannier-Stark regime has been reached only in artificial superlattices. Here we show that extremely transient bias over the few-femtosecond period of phase-stable mid-infrared pulses may localize electrons even in a bulk semiconductor like GaAs. The complicated band structure of a three-dimensional crystal leads to a strong blurring of field-dependent steps in the Wannier-Stark ladder. Only the central step emerges strongly in interband electro-absorption because its energetic position is dictated by the electronic structure at an atomic level and therefore insensitive to the external bias. In this way, we demonstrate an extreme state of matter with potential applications due to e.g., its giant optical non-linearity or extremely high chemical reactivity.

Quantitative Susceptibility Mapping after Sports-Related Concussion.

BACKGROUND AND PURPOSE: Quantitative susceptibility mapping using MR imaging can assess changes in brain tissue structure and composition. This report presents preliminary results demonstrating changes in tissue magnetic susceptibility after sports-related concussion. MATERIALS AND METHODS: Longitudinal quantitative susceptibility mapping metrics were produced from imaging data acquired from cohorts of concussed and control football athletes. One hundred thirty-six quantitative susceptibility mapping datasets were analyzed across 3 separate visits (24 hours after injury, 8 days postinjury, and 6 months postinjury). Longitudinal quantitative susceptibility mapping group analyses were performed on stability-thresholded brain tissue compartments and selected subregions. Clinical concussion metrics were also measured longitudinally in both cohorts and compared with the measured quantitative susceptibility mapping. RESULTS: Statistically significant increases in white matter susceptibility were identified in the concussed athlete group during the acute (24 hour) and subacute (day 8) period. These effects were most prominent at the 8-day visit but recovered and showed no significant difference from controls at the 6-month visit. The subcortical gray matter showed no statistically significant group differences. Observed susceptibility changes after concussion appeared to outlast self-reported clinical recovery metrics at a group level. At an individual subject level, susceptibility increases within the white matter showed statistically significant correlations with return-to-play durations. CONCLUSIONS: The results of this preliminary investigation suggest that sports-related concussion can induce physiologic changes to brain tissue that can be detected using MR imaging-based magnetic susceptibility estimates. In group analyses, the observed tissue changes appear to persist beyond those detected on clinical outcome assessments and were associated with return-to-play duration after sports-related concussion.

The absolute volume of PET-defined, active bone marrow spared predicts for high grade hematologic toxicity in cervical cancer patients undergoing chemoradiation

Introduction: Hematologic toxicity (HT) in cervical cancer patients can cause treatment delays and reduction in chemotherapy, especially in high risk patients. Dose to PET-defined regions of active bone marrow (ABM) has been shown to correlate with cytopenias. An absolute volume of ABM spared may accurately represent hematopoietic reserve and risk of HT. This analysis evaluates whether the volume of ABM spared can more accurately predict HT compared to conventional dosimetric parameters. Methods: Thirty-one patients treated for cervical cancer with chemoradiation from 9/2011 to 8/2016 were retrospectively reviewed. Receiver operating characteristic (ROC) curve were used to assess optimal cutpoint criterions for grade 3+ HT based on the CTCAEv4. Conventional dosimetric parameters to PBM and ABM (mean dose, V10, V20, V40) were assessed as well as the absolute volume (cc) of PBM and ABM spared 10, 20, and 40 Gy. Results: The absolute volume of PBM spared 10 Gy (< 230 cc; AUC 0.732, p = 0.03) as well as volume of ABM spared 10 Gy (< 179 cc; AUC 0.815, p = 0.0002), spared 20 Gy (< 186 cc; AUC 0.774, p = 0.0015), and spared 40 Gy (< 738 cc; AUC 0.887, p < 0.0001) all predicted grade 3+ HT. In patients with < 738 cc of ABM spared 40 Gy, 18/18 (100%) had grade 3+ toxicity compared to 6/13 (46%) of patients with > 738 cc of ABM spared 40 Gy (p < 0.0001). Conclusion: The baseline volume of ABM and the fraction of ABM present in patients vary significantly. The ongoing NRG-GY006 trial and other efforts at bone marrow sparing use V10, V20, and mean dose to the ABM during planning optimization. This analysis suggests that the volume of ABM spared 40 Gy (> 738 cc) may be a stronger predictor of HT than conventional dosimetric parameters. This should be further evaluated for clinical use

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Exotic complexes in one-dimensional Bose-Einstein condensates with spin-orbit coupling.

By means of the F-expansion method and intensive numerical simulations, the existence of three families of nonlinear matter waves including Jacobi elliptic functions, solitons, and triangular periodic functions, is demonstrated for spin-orbit coupled Bose-Einstein condensates with a linear potential. In addition, several complexes are obtained by taking two distinct solutions of each family or two distinct families. These solutions sustain different types of two-body interactions in the condensate that can be repulsive, attractive, or attractive and repulsive. Whereas the spin-orbit coupling destabilized these nonlinear matter waves, the linear potential leads to a stabilization. The numerical results are in excellent agreement with our analytical findings and it can be expected that the proposed robust solutions should be observable for experimentally relevant conditions.

[Drug-induced angioedema : Focus on bradykinin]. / Arzneimittelassoziierte Angioödeme : Bradykinin im Fokus.

On a pathophysiological level, angioedema can be differentiated into histamine- and bradykinin-mediated types. The prototype drug-associated, bradykinin-mediated form of angioedema is angiotensin-converting enzyme (ACE) inhibitor-induced angioedema. The hypothesized cause is a decrease in bradykinin degradation via ACE inhibition. In this scenario, other bradykinin-degrading enzymes assume major importance. When the effect of these enzymes is also diminished, e. g., due to genetic variants or external factors, compensation for the inhibition of ACE may be insufficient. An increased risk of angioedema has also been reported for other drugs, particularly when prescribed in combination with ACE inhibitors. Here, the suspected cause also relates to the degradation of bradykinin. When angioedema arises within the context of concomitant ACE inhibitor use, additive bradykinin degradation effects may be implicated.

Cortical abnormalities in bipolar disorder: an MRI analysis of 6503 individuals from the ENIGMA Bipolar Disorder Working Group.

Despite decades of research, the pathophysiology of bipolar disorder (BD) is still not well understood. Structural brain differences have been associated with BD, but results from neuroimaging studies have been inconsistent. To address this, we performed the largest study to date of cortical gray matter thickness and surface area measures from brain magnetic resonance imaging scans of 6503 individuals including 1837 unrelated adults with BD and 2582 unrelated healthy controls for group differences while also examining the effects of commonly prescribed medications, age of illness onset, history of psychosis, mood state, age and sex differences on cortical regions. In BD, cortical gray matter was thinner in frontal, temporal and parietal regions of both brain hemispheres. BD had the strongest effects on left pars opercularis (Cohen's d=-0.293; P=1.71 × 10-21), left fusiform gyrus (d=-0.288; P=8.25 × 10-21) and left rostral middle frontal cortex (d=-0.276; P=2.99 × 10-19). Longer duration of illness (after accounting for age at the time of scanning) was associated with reduced cortical thickness in frontal, medial parietal and occipital regions. We found that several commonly prescribed medications, including lithium, antiepileptic and antipsychotic treatment showed significant associations with cortical thickness and surface area, even after accounting for patients who received multiple medications. We found evidence of reduced cortical surface area associated with a history of psychosis but no associations with mood state at the time of scanning. Our analysis revealed previously undetected associations and provides an extensive analysis of potential confounding variables in neuroimaging studies of BD.

The absolute volume of PET-defined, active bone marrow spared predicts for high grade hematologic toxicity in cervical cancer patients undergoing chemoradiation.

INTRODUCTION: Hematologic toxicity (HT) in cervical cancer patients can cause treatment delays and reduction in chemotherapy, especially in high risk patients. Dose to PET-defined regions of active bone marrow (ABM) has been shown to correlate with cytopenias. An absolute volume of ABM spared may accurately represent hematopoietic reserve and risk of HT. This analysis evaluates whether the volume of ABM spared can more accurately predict HT compared to conventional dosimetric parameters. METHODS: Thirty-one patients treated for cervical cancer with chemoradiation from 9/2011 to 8/2016 were retrospectively reviewed. Receiver operating characteristic (ROC) curve were used to assess optimal cutpoint criterions for grade 3+ HT based on the CTCAEv4. Conventional dosimetric parameters to PBM and ABM (mean dose, V10, V20, V40) were assessed as well as the absolute volume (cc) of PBM and ABM spared 10, 20, and 40 Gy. RESULTS: The absolute volume of PBM spared 10 Gy (< 230 cc; AUC 0.732, p = 0.03) as well as volume of ABM spared 10 Gy (< 179 cc; AUC 0.815, p = 0.0002), spared 20 Gy (< 186 cc; AUC 0.774, p = 0.0015), and spared 40 Gy (< 738 cc; AUC 0.887, p < 0.0001) all predicted grade 3+ HT. In patients with < 738 cc of ABM spared 40 Gy, 18/18 (100%) had grade 3+ toxicity compared to 6/13 (46%) of patients with > 738 cc of ABM spared 40 Gy (p < 0.0001). CONCLUSION: The baseline volume of ABM and the fraction of ABM present in patients vary significantly. The ongoing NRG-GY006 trial and other efforts at bone marrow sparing use V10, V20, and mean dose to the ABM during planning optimization. This analysis suggests that the volume of ABM spared 40 Gy (> 738 cc) may be a stronger predictor of HT than conventional dosimetric parameters. This should be further evaluated for clinical use.

Dynamical Defects in Rotating Magnetic Skyrmion Lattices.

The chiral magnet Cu_{2}OSeO_{3} hosts a Skyrmion lattice that may be equivalently described as a superposition of plane waves or a lattice of particlelike topological objects. A thermal gradient may break up the Skyrmion lattice and induce rotating domains, raising the question of which of these scenarios better describes the violent dynamics at the domain boundaries. Here, we show that in an inhomogeneous temperature gradient caused by illumination in a Lorentz transmission electron microscope different parts of the Skyrmion lattice can be set into motion with different angular velocities. Tracking the time dependence, we show that the constant rearrangement of domain walls is governed by dynamic 5-7 defects arranging into lines. An analysis of the associated defect density is described by Frank's equation and agrees well with classical 2D Monte Carlo simulations. Fluctuations of boundaries show a surgelike rearrangement of Skyrmion clusters driven by defect rearrangement consistent with simulations treating Skyrmions as point particles. Our findings underline the particle character of the Skyrmion.

Bloch oscillations sustained by nonlinearity.

We demonstrate that nonlinearity may play a constructive role in supporting Bloch oscillations in a model which is discrete, in one dimension and continuous in the orthogonal one. The model can be experimentally realized in several fields of physics such as optics and Bose-Einstein condensates. We demonstrate that designing an optimal relation between the nonlinearity and the linear gradient strength provides extremely long-lived Bloch oscillations with little degradation. Such robust oscillations can be observed for a broad range of parameters and even for moderate nonlinearities and large enough values of linear potential. We also present an approximate analytical description of the wave packet's evolution featuring a hybrid Bloch oscillating wave-soliton behavior that excellently corresponds to the direct numerical simulations.

Global Burden of Sugar-Related Dental Diseases in 168 Countries and Corresponding Health Care Costs.

Oral diseases such as dental caries, edentulism (tooth loss), periodontal disease (PD), and oral cancer currently constitute an increased major public health burden across the globe, with significant differences between countries. One of the main drivers of caries, edentulism, and PD is the excessive intake of sugars. Here, we aimed to quantify the global sugar-related dental health and cost burden in the year 2010. This study used a health-econometrical model to calculate the disease burden as well as the direct and indirect costs attributable to the intake of free sugars (mono- and disaccharides [MDS]). To this end, several databases from the Institute for Health Metrics and Evaluation (IHME), Organisation for Economic Co-operation and Development (OECD), Food and Agriculture Organization (FAO), and World Bank were used. In total, the corresponding disease burden in 168 countries and economic burden in 31 OECD countries were quantified. In 2010, the consumption of MDS was associated with a global dental disease burden of 4.1 million disability-adjusted life years (DALYs; 95% uncertainty interval [UI]: 2.1 to 7.4 million DALYs), with 2.7 million DALYs from MDS-related caries and 1.4 million DALYs from PD. In terms of economic costs, MDS-related dental diseases were associated with a global financial burden of 172 billion US dollars (USD; 95% UI: 91 to 295 billion USD), the largest share of which (151 billion USD) was incurred in OECD countries. Overall, 26.3% (95% UI: 13.3% to 47.5%) of the total global oral disease burden was attributed to the consumption of MDS. The present study emphasizes the need to further address the role of free sugars in oral health and nutrition policy. Although the largest share of the economic burden was accounted for by OECD countries, emerging economies should address this challenge early on in national public health policies if they are to avoid disease and the prospect of increased cost burdens.

Tuning Spin Hall Angles by Alloying.

Within a combined experimental and theoretical study it is shown that the spin Hall angle of a substitutional alloy system can be continuously varied via its composition. For the alloy system Au_{x}Pt_{1-x} a substantial increase of the maximum spin Hall angle compared to the pure alloy partners could be achieved this way. The experimental findings for the longitudinal charge conductivity σ, the transverse spin Hall conductivity σ_{SH}, and the spin Hall angle α_{SH} could be confirmed by calculations based on Kubo's linear response formalism. Calculations of these response quantities for different temperatures show that the divergent behavior of σ and σ_{SH} is rapidly suppressed with increasing temperature. As a consequence, σ_{SH} is dominated at higher temperatures by its intrinsic contribution that has only a rather weak temperature dependence.

Dynamics of dipoles and vortices in nonlinearly coupled three-dimensional field oscillators.

The dynamics of a pair of harmonic oscillators represented by three-dimensional fields coupled with a repulsive cubic nonlinearity is investigated through direct simulations of the respective field equations and with the help of the finite-mode Galerkin approximation (GA), which represents the two interacting fields by a superposition of 3+3 harmonic-oscillator p-wave eigenfunctions with orbital and magnetic quantum numbers l=1 and m=1, 0, -1. The system can be implemented in binary Bose-Einstein condensates, demonstrating the potential of the atomic condensates to emulate various complex modes predicted by classical field theories. First, the GA very accurately predicts a broadly degenerate set of the system's ground states in the p-wave manifold, in the form of complexes built of a dipole coaxial with another dipole or vortex, as well as complexes built of mutually orthogonal dipoles. Next, pairs of noncoaxial vortices and/or dipoles, including pairs of mutually perpendicular vortices, develop remarkably stable dynamical regimes, which feature periodic exchange of the angular momentum and periodic switching between dipoles and vortices. For a moderately strong nonlinearity, simulations of the coupled-field equations agree very well with results produced by the GA, demonstrating that the dynamics is accurately spanned by the set of six modes limited to l=1.

Precession and nutation dynamics of nonlinearly coupled non-coaxial three-dimensional matter wave vortices.

Nonlinearity is the driving force for numerous important effects in nature typically showing transitions between different regimes, regular, chaotic or catastrophic behavior. Localized nonlinear modes have been the focus of intense research in areas such as fluid and gas dynamics, photonics, atomic and solid state physics etc. Due to the richness of the behavior of nonlinear systems and due to the severe numerical demands of accurate three-dimensional (3D) numerical simulations presently only little knowledge is available on the dynamics of complex nonlinear modes in 3D. Here, we investigate the dynamics of 3D non-coaxial matter wave vortices that are trapped in a parabolic potential and interact via a repulsive nonlinearity. Our numerical simulations demonstrate the existence of an unexpected and fascinating nonlinear regime that starts immediately when the nonlinearity is switched-on and is characterized by a smooth dynamics representing torque-free precession with nutations. The reported motion is proven to be robust regarding various effects such as the number of particles, dissipation and trap deformations and thus should be observable in suitably designed experiments. Since our theoretical approach, i.e., coupled nonlinear Schrödinger equations, is quite generic, we expect that the obtained novel dynamical behavior should also exist in other nonlinear systems.

Co-sputtered MoRe thin films for carbon nanotube growth-compatible superconducting coplanar resonators.

Molybdenum rhenium alloy thin films can exhibit superconductivity up to critical temperatures of T(c)=15K. At the same time, the films are highly stable in the high-temperature methane/hydrogen atmosphere typically required to grow single wall carbon nanotubes. We characterize molybdenum rhenium alloy films deposited via simultaneous sputtering from two sources, with respect to their composition as function of sputter parameters and their electronic dc as well as GHz properties at low temperature. Specific emphasis is placed on the effect of the carbon nanotube growth conditions on the film. Superconducting coplanar waveguide resonators are defined lithographically; we demonstrate that the resonators remain functional when undergoing nanotube growth conditions, and characterize their properties as function of temperature. This paves the way for ultra-clean nanotube devices grown in situ onto superconducting coplanar waveguide circuit elements.

High-sensitivity NMR beyond 200,000 atmospheres of pressure.

Pressure-induced changes in the chemical or electronic structure of solids require pressures well into the Giga-Pascal (GPa) range due to the strong bonding. Anvil cell designs can reach such pressures, but their small and mostly inaccessible sample chamber has severely hampered NMR experiments in the past. With a new cell design that has a radio frequency (RF) micro-coil in the high pressure chamber, NMR experiments beyond 20 Giga-Pascal are reported for the first time. (1)H NMR of water shows sensitivity and resolution obtained with the cells, and (63)Cu NMR on a cuprate superconductor (YBa2Cu3O7-δ) demonstrates that single-crystals can be investigated, as well. (115)In NMR of the ternary chalcogenide AgInTe2 discovers an insulator-metal transition with shift and relaxation measurements. The pressure cells can be mounted easily on standard NMR probes that fit commercial wide-bore magnets with regular cryostats for field- and temperature-dependent measurements ready for many applications in physics and chemistry.

Fast electrically assisted regeneration of on-chip SERS substrates.

A microfluidic chip approach utilising integrated electrically connected stationary SERS targets based on inkjet-printed silver nanoparticles is presented. It enables multiple interference-free consecutive surface-enhanced Raman measurements inside chip channels by electrically assisted regeneration of the stationary SERS substrate. Thereby it circumvents common adsorption and memory effect problems associated with stationary SERS targets allowing multiple consecutive measurements in a continuous-flow system.