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Advancement in the design of large high-speed ferries demands comprehensive knowledge of ship motions and wave-induced loads to optimise their structural integrity. This investigation focused on the fluid structure-interaction problem experimentally to obtain such information. Motions and loads were investigated by using two different high-speed catamaran models and a full scale ship. Firstly, a hydroelastic segmented model (HSM) of the INCAT 112 m class wavepiercer catamaran with centrebow was designed. It was tested in a towing tank for a range of head seas conditions to determine the motion responses, vertical bending moment (VBM) and slam loads. A second catamaran model was designed and tested in oblique seas in a model test basin (MTB) to examine the motions and asymmetric wave-induced loads. Thirdly, full scale measurements were performed during the delivery voyage of the INCAT 112 m Hull 064 from Hobart in Australia to Hakodate in Japan, to measure the motions and structural load responses. The structural dynamic behaviour of the full scale vessel was replicated by the HSM model and the slamming and subsequent whipping behaviour were successfully modelled. As wave energy was consumed in the structural vibration of the model, the heave and pitch transfer function peaks reduced significantly when compared to the rigid configuration. The HSM test results also showed a strong non-linear motion response, with respect to wave height for this type of vessel, mainly due to the influence of the centrebow. The peak values for the VBM and slam loads were confirmed to be proportional to the square of the wave height for large waves. The MTB test model, which was not fitted with a centrebow, provided linear pitch, heave and roll motions for varying wave heights. The pitch connecting moment was found to be the dominant of the asymmetric wave loads and was linear with respect to wave height. During the full scale measurement programme, slamming phenomena were clearly recorded whilst crossing the Bass Strait. A reconstruction of the event, from the measured data, indicated that a slam event with subsequent whipping occurred with a bow down trim. Spectral analysis was used to detect the response frequencies of the VBM and machinery, with the frequency of the longitudinal mode increasing as the displacement reduced. These experimental programmes, encompassing model and full scale measurements, have revealed valuable insights into the motion and structural dynamic behaviour of large high-speed catamarans. A comprehensive set of motion transfer functions, VBM and slam loads coefficients have been obtained, thus providing designers with important slam and wave load knowledge to aid the improved structural optimisation of these vessels.

Objective: To investigate the safety and effectiveness of direct oral anticoagulants (DOAC) versus vitamin K antagonists (VKA) after recent stroke in patients with atrial fibrillation (AF) aged ≥85 years. Methods: Individual patient data analysis from seven prospective stroke cohorts. We compared DOAC versus VKA treatment among patients with AF and recent stroke (≥85y = 0.65, 95%-CI [0.52, 0.81]) and < 85 years (HR = 0.79, 95%-CI [0.66, 0.95]) in simple (p interaction = 0.129), adjusted (p interaction = 0.094) or weighted (p interaction = 0.512) models. Analyses on recurrent stroke, ICH and death separately were consistent with the primary analysis, as were sensitivity analyses using age dichotomized at 90 years and as a continuous variable. DOAC had a similar net clinical benefit in patients aged ≥85 (+1.73 to +2.66) and < 85 years (+1.90 to +3.36 events/100 patient-years for ICH-weights 1.5 to 3.1). Interpretation: The favorable profile of DOAC over VKA in patients with AF and recent stroke was maintained in the oldest old. ANN NEUROL 2021.

Objective: To investigate the safety and effectiveness of direct oral anticoagulants (DOAC) versus vitamin K antagonists (VKA) after recent stroke in patients with atrial fibrillation (AF) aged ≥85 years. Methods: Individual patient data analysis from seven prospective stroke cohorts. We compared DOAC versus VKA treatment among patients with AF and recent stroke (

Chlorophyll a fluorescence is a powerful indicator of photosynthetic energy conversion in plants and photosynthetic microorganisms. One of the most widely used measurement techniques is Pulse Amplitude Modulation (PAM) fluorometry. Unfortunately, parameter settings of PAM instruments are often not completely described in scientific articles although their variations, however small these may seem, can influence measurements. We show the effects of parameter settings on PAM measurements. We first simulated fluorescence signals using a previously published computational model of photosynthesis. Then, we validated our findings experimentally. Our analysis demonstrates how the kinetics of non-photochemical quenching (NPQ) induction and relaxation are affected by different settings of PAM instrument parameters. Neglecting these parameters may mislead data interpretation and derived hypotheses, hamper independent validation of the results, and cause problems for mathematical formulation of underlying processes. Given the uncertainties inflicted by this neglect, we urge PAM users to provide detailed documentation of measurement protocols. Moreover, to ensure accessibility to the required information, we advocate minimum information standards that can serve both experimental and computational biologists in our efforts to advance system-wide understanding of biological processes. Such specification will enable launching a standardized database for plant and data science communities.HighlightPAM fluorometry measurement is sensitive to instrument settings and protocols. Yet, protocols are published incompletely. We urge to reach an agreement on minimal protocol information of PAM experiments to be shared publicly.

We developed equations to predict the asymptotic response due to two-stage selection, where first-stage selection was performed by using GEBVs based solely on genotypes and second-stage selection was performed with GEBVs that combined genotypes and phenotypes. The situation that we considered involved four-path selection executed as sires to breed sons, sires to breed daughters, dams to breed sons, and dams to breed daughters. We established two procedures to predict the response. The first incorporated correlated indices during the first and second-stage selections of two-stage selection. The other procedure used independent indices during two-stage selection. The response per generation in the initial generation was greater for the correlated indices than for the independent indices. However, the asymptotic response per generation was slightly greater for the independent indices than for the correlated indices. The asymptotic response per generation was lower during two-stage selection than during single-stage selection. However, the asymptotic response per year was greater for two-stage selection than for single-stage selection. In addition, that trend was more conspicuous when the economic weight was 1:3 for the first (h2 =0.3) to second (h2 =0.05) index trait compared with economic weights of 1:1 and 3:1. However, the magnitude of the response to the aggregate genotype-relative not to single-stage selection but to absolute magnitude was greater at an economic weight of 3:1 than at those of 1:1 and 1:3. The reduction in genetic variance from the initial to an asymptotic generation was greater for a scenario where young parents selected at the first-stage accounted for 30% of all parents in two-stage selection than where they accounted for 70%. The reduction in genetic variance of the aggregate genotype over generations was smaller for independent indices than correlated indices during two-stage selection. Our new formula for predicting genetic response applies to any combination of accuracies of GEBVs and intensities of selection. Therefore, the formula presented is a general equation for predicting genetic response over generations due to two-stage genomic index selection.