Dispersive wave runup on non-uniform shores

Historically the finite volume methods have been developed for the numerical integration of conservation laws. In this study we present some recent results on the application of such schemes to dispersive PDEs. Namely, we solve numerically a representative of Boussinesq type equations in view of important applications to the coastal hydrodynamics. Numerical results of the runup of a moderate wave onto a non-uniform beach are presented along with great lines of the employed numerical method (see D. Dutykh et al. (2011) for more details).Comment: 8 pages, 6 figures, 18 references. This preprint is submitted to FVCA6 conference proceedings. Other author papers can be downloaded at http://www.lama.univ-savoie.fr/~dutykh

Neutron spin structure from e-3He scattering with double spectator tagging at the electron-ion collider

The spin structure function of the neutron is traditionally determined by measuring the spin asymmetry of inclusive electron deep inelastic scattering (DIS) off polarized 3He nuclei. In such experiments, nuclear corrections are significant and must be treated carefully in the interpretation of experimental data. Here we study the feasibility of suppressing model dependencies by tagging both spectator protons in the process of DIS off neutrons in 3He at the forthcoming Electron-Ion Collider (EIC). This allows for a reconstruction of the momentum of the struck neutron to ensure it was nearly at rest in the initial state, thereby reducing sensitivity to nuclear corrections and suppressing contributions from electron DIS off protons in 3He. Using realistic accelerator and detector configurations, we demonstrate that the EIC can probe the neutron spin structure from xB of 0.003 to 0.651. We find that the double spectator tagging method results in reduced uncertainties by a factor of 2 on the extracted neutron spin asymmetries over all kinematics and by a factor of 10 in the low-xB region, thereby providing valuable insight into the spin and flavor structure of nucleons

Neutron spin structure from e-3He scattering with double spectator tagging at the electron-ion collider

The spin structure function of the neutron is traditionally determined by measuring the spin asymmetry of inclusive electron deep inelastic scattering (DIS) off polarized3He nuclei. In such experiments, nuclear effects can lead to large model dependencies in the interpretation of experimental data. Here we study the feasibility of suppressing such model dependencies by tagging both spectator protons in the process of DIS off neutrons in3He at the forthcoming Electron-Ion Collider (EIC). This allows reconstructing the momentum of the struck neutron to ensure it was nearly at rest in the initial state, thereby reducing sensitivity to nuclear corrections, and suppress contributions from electron DIS off protonsin3He. Using realistic accelerator and detector configurations, we find that the EIC can probe the neutron spin structure from xB of 0.003 to 0.651. We further find that the double spectator tagging method results in reduced uncertainties bya factor of 4 on the extracted neutron spin asymmetries over all kinematics, and by a factor of 10 in the low-xB region,thereby providing valuable insight to the spin and flavor structure of nucleonsComment: 8 pages, 5 figure

Optimal Testing Intervals in the Squatting Test to Determine Baroreflex Sensitivity

The recently introduced “squatting test” (ST) utilizes a simple postural change to perturb the blood pressure and to assess baroreflex sensitivity (BRS). In our study, we estimated the reproducibility of and the optimal testing interval between the STs in healthy volunteers. Thirty-four subjects free of cardiovascular disorders and taking no medication were instructed to perform the repeated ST at 30-sec, 1-min, and 3-min intervals in duplicate in a random sequence, while the systolic blood pressure (SBP) and pulse intervals were measured. Baroreflex sensitivity was estimated by plotting reflex increases and decreases in the SBP and succeeding pulse intervals during stand-to-squat and squat-to-stand maneuvers, respectively. Correlations between duplicate BRS data at each testing interval were analyzed by the Pearson’s correlation coefficient, while agreements were assessed by Bland-Altman plots. Two measurements of BRS during stand-to-squat and squat-to-stand maneuvers demonstrated significant correlations at both 1-min and 3-min intervals, while at 30-sec intervals correlation was poor. Correlation coefficients became considerably greater in each maneuver as the measurement interval was increased from 30 sec to 3 min. Our results suggest that the testing interval in the ST should be at least 1 min long, but ideally it should be longer than or equal to 3 min, to assess the baroreflex adequately.У нещодавно запропонованому «тесті присідання» (ТП) використовується проста зміна пози для індукції зрушення кров’яного тиску, що дозволяє визначити барорефлекторну чутливість (БРЧ). Ми оцінювали ступінь відтворюваності та оптимальні інтервали між ТП, що реалізовувалися здоровими випробуваними. Групу з 34 тестованих, які не мали будь-яких серцево-судинних розладів та не приймали якихось ліків, інструктували виконувати повторні подвійні ТП у випадковій послідовності з інтервалами 30 с, 1 та 3 хв; при цьому вимірювали систолічний кров’яний тиск (СКТ) та кардіоінтервали. Рефлекторні підвищення та зниження СКТ і послідовні кардіоінтервали під час рухів присідання та повернення у вертикальну позу представляли графічно. Залежність між повторними визначеннями БРЧ при кожному інтервалі між тестами аналізували, встановлюючи коефіцієнти кореляції Пірсона. Виміри БРЧ під час рухів присідання та підйому демонстрували істотну кореляцію при інтервалах 1 та 3 хв, а при інтервалах 30 с кореляція була слабшою. Коефіцієнти кореляції ставали помітно значнішими з кожним рухом і збільшенням інтервалів між вимірами від 30 с до 3 хв. Наші результати вказують на те, що адекватна оцінка барорефлексу може бути забезпечена при інтервалах між ТП не менше 1 хв (бажано 3 хв або більше)

Revealing the structure of light pseudoscalar mesons at the electron-ion collider

The questions of how the bulk of the Universe's visible mass emerges and how it is manifest in the existence and properties of hadrons are profound, and probe the heart of strongly interacting matter. Paradoxically, the lightest pseudoscalar mesons appear to be key to a further understanding of the emergent mass and structure mechanisms. These mesons, namely, the pion and kaon, are the Nambu-Goldstone boson modes of quantum chromodynamics (QCD). Unravelling their partonic structure and the interplay between emergent and Higgs-boson mass mechanisms is a common goal of three interdependent approaches - continuum QCD phenomenology, lattice-regularised QCD, and the global analysis of parton distributions - linked to experimental measurements of hadron structure. Experimentally, the anticipated electron-ion collider will enable a revolution in our ability to study pion and kaon structures, accessed by scattering from the 'meson cloud' of the proton through the Sullivan process. With the goal of enabling a suite of measurements that can address these questions, we examine key reactions that identify the critical detector-system requirements needed to map tagged pion and kaon cross-sections over a wide range of kinematics. The excellent prospects for extracting pion structural, functional, and form-factor data are outlined, and similar prospects for kaon structures are discussed in the context of a worldwide programme. The successful completion of the programme outlined herein will deliver deep, far-reaching insights into the emergence of pions and kaons, their properties, and their role as QCD's Goldstone boson modes