The Mercury Imaging X-ray Spectrometer (MIXS) on the BepiColombo Mercury Planetary Orbiter (MPO) will measure fluorescent X-ray emission from the surface of Mercury in the energy range 0.5–7.5
keV, ...which is induced by incident solar X-rays and solar wind electrons and protons. These X-rays will reveal the elemental composition of the surface of Mercury and aid the determination of the planet's evolution.
MIXS is a two component instrument. A collimated channel (MIXS-C) provides measurements on scales of 70–270
km, sufficient to separate the major Mercurian terrains. A second channel (MIXS-T) is the first imaging X-ray telescope for planetary remote sensing and will make measurements on spatial scales of less than 10
km for major elements during solar flares, sufficient to isolate surface landforms, such as craters and their internal structures. The spatial resolution achieved by MIXS-T is made possible by novel, low mass microchannel plate X-ray optics, in a Wolter type I optical geometry.
MIXS measurements of surface elemental composition will help determine rock types, the evolution of the surface and ultimately a probable formation process for the planet. In this paper we present MIXS and its predicted performance at Mercury as well as discussing the role that MIXS measurements will play in answering the major questions about Mercury.
Numerical simulations using the Finite-Difference Time-Domain method were used to study the propagation of an acoustic wave within a truncated ellipsoidal cavity. Based in our simulations, a fluidic ...device was designed and fabricated using a 3D printer in order to focus an acoustic wave more efficiently and expel a liquid jet. The device consists of an ellipsoidal shaped chamber filled with a highly absorbent solution at the operating wavelength (1064 nm) in order to create a vapor bubble using a continuous wavelength laser. The bubble rapidly expands and collapses emitting an acoustic wave that propagates inside the cavity, which was measured by using a needle hydrophone. The bubble collapse, and source of the acoustic wave, occurs in one focus of the cavity and the acoustic wave is focused on the other one, expelling a liquid jet to the exterior. The physical mechanism of the liquid jet generation is momentum transfer from the acoustic wave, which is strongly focused due to the geometry of the cavity. This mechanism is different to the methods that uses pulsed lasers for the same purpose. The maximum speed of the generated liquid microjets was approximately 20 m/s. One potential application of this fluidic device can be found for inkjet printing, coating and, maybe the most attractive, for drug delivery.
Most serious complications of infective endocarditis (IE) appear in the so-called "critical phase" of the disease, which represents the first days after diagnosis. The majority of patients overcoming ...the acute phase has a favorable outcome, yet they remain hospitalized for a long period of time mainly to complete antibiotic therapy. The major hypothesis of this trial is that in patients with clinically stable IE and adequate response to antibiotic treatment, without signs of persistent infection, periannular complications or metastatic foci, a shorter antibiotic time period would be as efficient and safe as the classic 4 to 6 weeks antibiotic regimen. Multicenter, prospective, randomized, controlled open-label, phase IV clinical trial with a non-inferiority design to evaluate the efficacy of a short course (2 weeks) of parenteral antibiotic therapy compared with conventional antibiotic therapy (4-6 weeks). SATIE will investigate whether a two weeks short-course of intravenous antibiotics in patients with IE caused by gram-positive cocci, without signs of persistent infection, is not inferior in safety and efficacy to conventional antibiotic treatment (4-6 weeks).
Superelastic nanocompression tests are performed on different micropillars milled by focused ion beam from 001-oriented single crystals of Cu–Al–Ni shape memory alloys. Over hundreds of cycles such ...micropillars exhibit reproducible superelastic behavior with complete recovery at stresses around 300MPa and stress-induced transformation strains above 5%. Upon cycling, the critical stress to induce the transformation decreases, and the transformation strain increases, both signatures of a training effect which is analyzed here in terms of the microscopic mechanisms controlling the nucleation, growth and recovery of the martensite plates. The mechanical hysteresis is characterized through the energy dissipated during closed superelastic cycles, and its evolution during cycling is discussed. The superelastic cycling of the micropillars is also found to depend on the strain rate. The highest strain rate studied here, 10−1s−1, is found to impinge upon the nucleation and growth kinetics of γ3′ and β3′ martensites, with the result that the mechanical hysteresis and transformation strain are reduced. Finally, specific cycling tests have been conducted at increasing maximum loads to analyze the limit for plastic deformation of the micropillar, which happens between 500 and 700MPa.
Confirming the prognostic value of global QFR and evaluating the long-term prognosis of QFR-concordant therapy in stable coronary artery disease.
Wire-based functional evaluation of coronary disease ...is linked to patient's prognosis. Quantitative Flow Ratio (QFR) is a newer index of computational physiology, linked to clinical outcomes and prognosis at 1 year follow-up. Long-term prognosis of QFR-concordant revascularization in stable coronary artery disease is however unknown hitherto.
Consecutive patients with stable coronary disease undergoing coronary angiography were included. Centralized and blinded QFR analysis of three coronary territories was performed. Three vessel QFR (3vQFR) was defined as the sum of the basal QFR of each coronary territory. QFR-concordant revascularization was met if all significant lesions (QFR ≤ 0.80) were revascularized and all non-significant lesions (QFR > 0.80) were not; otherwise, the case was defined as QFR-discordant revascularization. Patient-oriented composite end-point (POCE) of cardiac death, myocardial infarction and unscheduled revascularization was the primary endpoint.
A total of 803 patients from six high-volume centers were included. Canadian Cardiovascular Society (CCS) class II angina was the most frequent (48.9%) clinical presentation. Median of follow-up was 68.8 months. 3vQFR was an independent predictor of POCE (HR 1.79 CI95% 1.01–3.18), with 2.75 as optimal cut-off value, irrespective of the therapy received. QFR-discordant revascularization (QFR+/Revascularization- or QFR-/Revascularization+) was an independent predictor of POCE in multivariate analysis (HR 1.65, CI 95% 1.03–2.64).
Global burden of epicardial coronary atherosclerosis, as evaluated by 3vQFR, as well as QFR-discordant therapy are independent predictors of adverse clinical outcome at long-term follow-up in stable coronary artery disease.
•What is known about de topic?•Guiding coronary revascularization by wire-based indexes of physiology, as FFR or iFR, translates into improved clinical outcomes in multiple scenarios of stable coronary artery disease.•Global burden or coronary artery disease, as assessed by coronary physiology, is a prognostic factor of outcomes, irrespective of the therapy received guided mainly by visual estimation.•What does this study add?•Coronary revascularization performed in concordance with angiography-based computational physiology (QFR), without need for a specific pressure-wire insertion and without induction of hyperaemia, translates also into long-term clinical outcomes in stable coronary disease (up to 5 years of follow-up).•Global burden or coronary artery disease, as assessed by QFR, has similar prognostic value to other indexes of physiology in the long term, irrespective of the therapy received.
Several orthotopic transcatheter strategies have been developed to treat severe tricuspid regurgitation (TR); however, many patients are deemed unsuitable. Caval valve implantation with the TricValve ...system addresses this unmet need.
This study sought to determine the impact of TricValve on systemic congestion and quality of life (QOL) at 1 year.
The TRICUS (Safety and Efficacy of the TricValve® Transcatheter Bicaval Valves System in the Superior and Inferior Vena Cava in Patients With Severe Tricuspid Regurgitation) and TRICUS EURO studies were prospective, nonblinded, nonrandomized, single-arm trials representing the early-in-man experience of the TricValve system in NYHA functional class III or IV severe TR patients, optimally medicated and ineligible for open heart surgery, with significant caval backflow. The primary endpoint was QOL metrics and functional status. The 1-year results of the combined cohort are described here.
Forty-four patients were included. Mean age was 76.2 ± 7.5 years, 81.0% were women, and the TRISCORE (risk score model for isolated tricuspid valve surgery) was 5.3 ± 1.3. Clinical improvement at 1 year was achieved in 42 (95.5%) patients, measured by (at least 1 of) an increase in ≥15 points from baseline in 12-item Kansas City Cardiomyopathy Questionnaire score, improvement to NYHA functional class to I or II, or an increase ≥40 m in the 6-minute walk test. There were 3 (6.8%) deaths at 1-year follow-up (1 cardiovascular), and the heart failure rehospitalization rate was 29.5%. Stent fracture, conduction system disturbances, or clinically significant leaflet thrombosis were not detected. Abolished hepatic vein backflow was achieved and persisted in 63.8% of the patients, contributing towards a reduction in congestive symptoms, N-terminal pro-B-type natriuretic peptide levels (P = 0.032), and diuretic treatment.
Caval valve implantation with the TricValve system associated with meaningful 1-year clinical improvements in terms of QOL along with relatively low mortality rates. (TRICUS Study - Safety and Efficacy of the TricValve® Device; NCT03723239).
Microalgae is highlighted as the most feasible bioenergy feedstock because it can produce high amounts of lipids, carbohydrates, and hydrogen, which are necessary compounds for the production of ...various biofuels, while only requiring minimal water and land due to high photosynthetic efficiency. However, there are technical limitations that negatively influence the mass production of biofuel from algae, making it economically infeasible on a commercial scale. One of these bottlenecks exist in its cultivation. The cultivation method and system are critical in determining the amount and quality of biofuel that may be generated from the microalgae. Additionally, the peak biomass concentration, and productivities for the different compounds and nutrients within microalgae do not occur at the same time. Hence, this work proposes a planning tool for microalgae cultivation systems that incorporates species selection, and cultivation and harvesting approach selection and scheduling, while balancing the minimization of environmental impact and maximization of profit realized. The capabilities of the proposed decision support model is demonstrated through a hypothetical case study. Scenario analyses is likewise conducted to establish an understanding of system behavior and performance over time and under various conditions. The results of the computational experiments show the tools capabilities in simultaneously considering algae growth rates and compound productivities in decision making, for instance biomass species that is able to generate the most of a certain high value fuel is prioritized in cultivation and harvesting.
► Shape memory alloys exhibit different properties at nano-scale than in bulk materials. ► An overview of the size-effects at nano-scale on the martensitic transformation is presented. ► The ...size-effects observed on the superelastic behavior at nano-scale are explained in terms of the microscopic mechanisms operating at this small scale.
In this work we overview the extrinsic size-effects on the martensitic transformation reported in the literature by nano compression tests in micro and sub-micrometer pillars, as well as by in situ superelastic tests at the transmission electron microscope. Three different size-effects are described: The increase of the critical stress for superelasticity at nano scale, the decrease of the stress for recovery during the reverse stress-induced martensitic transformation at micro and nano scale and finally the change of the selection rule for the martensitic variants promoted at micro and nano scale. New results are presented to illustrate the behavior of these size-effects and the microscopic origin of such effects is discussed. A consistent interpretation is given and explained for each one of the reported size-effects on the martensitic transformation.
PDF
