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The objective of this work was to study the elastic recovery of EPDM samples crosslinked either by a phenolic resin (resol) or by a radical peroxide (dicumyl peroxide, DCP). From compression set experiments, it was observed that radically crosslinked EPDMs have better elastic recovery properties. On the other hand, for the same crosslinking density, radically crosslinked EPDM shows better compression set than EPDM crosslinked with phenolic resins. The Chasset-Thirion equation was then used to successfully fit the experimental relaxation curves. As a notable result, the preferential statistics of a peroxide-crosslinked network over a phenolic resin (resol) showed that better elastic recovery properties were obtained. Finally, the influence of fillers (carbon black and silica) was also studied. Carbon black with DCP crosslinking was shown to improve elasticity recovery whereas silica fillers lead to worse properties. It was then assumed that the interaction between particle surface and a voir comme dans autre publi à modifier ce crosslinking agent induced crosslinking gradients in the inter-particle volume. [ABSTRACT FROM AUTHOR]

The S1222a marsquake detected by InSight on 4 May 2022 was the largest of the mission, at MwMa ${M}_{w}^{Ma}$ 4.7. Given its resemblance to two other large seismic events (S1000a and S1094b), which were associated with the formation of fresh craters, we undertook a search for a fresh crater associated with S1222a. Such a crater would be expected to be ∼300 m in diameter and have a blast zone on the order of 180 km across. Orbital images were targeted and searched as part of an international, multi‐mission effort. Comprehensive analysis of the area using low‐ and medium‐resolution images reveals no relevant transient atmospheric phenomena and no fresh blast zone. High‐resolution coverage of the epicentral area from most spacecraft are more limited, but no fresh crater or other evidence of a new impact have been identified in those images either. We thus conclude that the S1222a event was highly likely of tectonic origin. Plain Language Summary: During its time on Mars, NASA's InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) mission recorded over 1,300 seismic events, known as "marsquakes." Of these, a number were identified as coming from meteoroid impact cratering events on the surface. The largest event identified by InSight, labeled S1222a, bore some similarities to two large impact events recorded earlier in the mission. In order to investigate whether the S1222a event might also have been caused by an impact event, we undertook a comprehensive search of the region in which the marsquake occurred. We did not identify any fresh craters in the area, implying that the marsquake was likely caused by geological processes. Key Points: The S1222a marsquake detected by InSight on 4 May 2022 somewhat resembled previous impact‐generated eventsWe performed an image search in the estimated source region, using data from multiple Mars orbiter missionsNo new impact crater has been discovered in this area, pointing to a tectonic origin for the quake [ABSTRACT FROM AUTHOR]

The purpose of this work is to present a patient‐specific (PS) modeling approach for simulating percutaneous transluminal angioplasty (PTA) endovascular treatment and assessing the balloon sizing influence on short‐term outcomes in peripheral arteries, i.e. without stent implantation. Two 3D PS stenosed femoral artery models, one with a dominant calcified atherosclerosis while the other with a lipidic plaque, were generated from pre‐operative computed tomography angiography images. Elastoplastic constitutive laws were implemented within the plaque and artery models. Implicit finite element method (FEM) was used to simulate the balloon inflation and deflation for different sizings. Besides vessel strains, results were mainly evaluated in terms of the elastic recoil ratio (ERR) and lumen gain ratio (LGR) attained immediately after PTA. Higher LGR values were shown within the stenosed region of the lipidic patient. Simulated results also showed a direct and quantified correlation between balloon sizing and LGR and ERR for both patients after PTA, with a more significant influence on the lumen gain. The max principal strain values in the outer arterial wall increased at higher balloon sizes during inflation as well, with higher rates of increase when the plaque was calcified. Results show that our model could serve in finding a compromise for each stenosis type: maximizing the achieved lumen gain after PTA, but at the same time without damaging the arterial tissue. The proposed methodology can serve as a step toward a clinical decision support system to improve angioplasty balloon sizing selection prior to the surgery. [ABSTRACT FROM AUTHOR]

• We tested 7 types of turbidity sensors for concentrations in the range 0.05–100 g/L. • Measurements per sensor showed a tenfold variation among 12 sediment types. • Complementary scattering signals may allow for an extended SSC monitoring range, • and/or reduced sensitivity to covarying physical properties of river sediment. • Sensors are increasingly sensitive to sediment colour for concentrations > 10 g/L. To monitor the effects of rapid changes in climate and land use on sediment export from erodible environments, it is crucial to accurately quantify highly fluctuating suspended sediment concentrations (SSCs) in contrasted river systems that drain small to mesoscale catchments. To this end, we investigate the turbidity-based quantification of SSCs in the range of 0.05–100 g/L through laboratory experiments performed with 7 different types of turbidity sensors and sediments from 10 watersheds. We find that measurements of scattered light from multiple angles may allow for: (1) an extended monitoring range with SSCs up to 10–100 g/L, where enhanced uncertainty may occur near the transition in the effective operational ranges of the underlying signals (typically somewhere in the range of 1–10 g/L); and/or (2) a slightly reduced sensitivity to sediment properties. The specific turbidity of the investigated sensors is inversely related to particle diameter (D 10) for SSCs up to 1–5 g/L. Backscatter and combined-signal sensors also show a dependency on sediment colour (CIE a ∗ ), which becomes particularly prominent at SSCs above 10 g/L. We relate this increase in colour dependency with SSC to the expected effect of cumulative near-infrared light absorption associated with multiple scattering. We discuss covarying physical properties of naturally occurring river sediment that can dampen or enhance measurement sensitivity and result in turbidity-based SSC rating curves that may strongly differ in magnitude and form from curves derived for industrially prepared material that is often used for sensor calibration. Although the differences in SSC per sensor among sediment types are generally less than one order of magnitude, the systematic errors and uncertainties associated with high SSCs are typically greater than one order of magnitude and may disproportionally affect the quantification of sediment loads during large-magnitude flow events. [ABSTRACT FROM AUTHOR]

Unraveling the stratigraphic record is the key to understanding ancient climate and past climate changes on Mars ( Grotzinger, J. et al. [2011]. Astrobiology 11, 77–87 ). Stratigraphic records of river deposits hold particular promise because rain or snowmelt must exceed infiltration plus evaporation to allow sediment transport by rivers. Therefore, river deposits when placed in stratigraphic order could constrain the number, magnitudes, and durations of the wettest (and presumably most habitable) climates in Mars history. We use crosscutting relationships to establish the stratigraphic context of river and alluvial-fan deposits in the Aeolis Dorsa sedimentary basin, 10°E of Gale crater. At Aeolis Dorsa, wind erosion has exhumed a stratigraphic section of sedimentary rocks consisting of at least four unconformity-bounded rock packages, recording three or more distinct episodes of surface runoff. Early deposits (>700 m thick) are embayed by river deposits (>400 m thick), which are in turn unconformably draped by fan-shaped deposits (<100 m thick) which we interpret as alluvial fans. Yardang-forming layered deposits (>900 m thick) unconformably drape all previous deposits. River deposits embay a dissected landscape formed of sedimentary rock. The river deposits are eroding out of at least two distinguishable units. There is evidence for pulses of erosion during the interval of river deposition. The total interval spanned by river deposits is >(1 × 10 6 –2 × 10 7 ) yr, and this is extended if we include alluvial-fan deposits. Alluvial-fan deposits unconformably postdate thrust faults which crosscut the river deposits. This relationship suggests a relatively dry interval of >4 × 10 7 yr after the river deposits formed and before the fan-shaped deposits formed, based on probability arguments. Yardang-forming layered deposits unconformably postdate all of the earlier deposits. They contain rhythmite and their induration suggests a damp or wet (near-) surface environment. The time gap between the end of river deposition and the onset of yardang-forming layered deposits is constrained to >1 × 10 8 yr by the high density of impact craters embedded at the unconformity. The time gap between the end of alluvial-fan deposition and the onset of yardang-forming layered deposits was at least long enough for wind-induced saltation abrasion to erode 20–30 m into the alluvial-fan deposits. We correlate the yardang-forming layered deposits to the upper layers of Gale crater’s mound (Mt. Sharp/Aeolis Mons), and the fan-shaped deposits to Peace Vallis fan in Gale crater. Alternations between periods of low mean obliquity and periods of high mean obliquity may have modulated erosion–deposition cycling in Aeolis. This is consistent with the results from an ensemble of simulations of Solar System orbital evolution and the resulting history of the obliquity of Mars. 57 of our 61 simulations produce one or more intervals of continuously low mean Mars obliquity that are long enough to match our Aeolis Dorsa unconformity data. [ABSTRACT FROM AUTHOR]

Simple Summary: Hematophagous flies are a pest for livestock due to their bites, annoyance and the diseases they transmit. Cattle exposed to biting flies exhibit defence movements such as tail flicks. The evaluation of biting fly density and annoyance by counting tail flicks of cattle has been validated in the past, but it is highly time consuming. In this study, we evaluated the use of sport pedometers attached to the tails of feeder cattle, in order to evaluate tails flick frequency in two groups of six feeder cattle: Group A was protected by a mosquito net, and Group B was in open-air. Tail flicks were also recorded visually. In addition, insect density was evaluated using three fly traps in the surrounding of Group B. A strong correlation was observed between fly density and visual records of tail flicks; a stronger correlation was found between fly density and tail pedometer records. The reports of tail flicks at night were even able to draw attention to a huge infestation by mosquitoes. Finally, in these experimental conditions, tail pedometers proved to be useful tools in evaluating density and the impact of dipterans on cattle behaviour. They will be useful tools to evaluate new biting fly control methods. Hematophagous flies are a pest for livestock; their direct impact reduces productivity, and they are vectors of parasites, bacteria and viruses. Their control using insecticides is inefficient and highly polluting. The validation of new control tools requires efficacy and cost-effectiveness evaluation. The quantification of hematophagous insects' impact in livestock is a challenging prerequisite. Tail flicks counts can reliably evaluate fly-burden; however, visual records are tedious and time-consuming. In the present study, automation of tail flick counts was made through the use of pedometers attached to the tail, in two groups of feeder cattle. Group A was kept in a pen under the protection of a mosquito net, and Group B was kept in an open-air pen. The fly density of Group B was evaluated using fly traps. The apparent density per trap ranged from 130 to 1700 in the study. The mean pedometer records per 24 h ranged from 957+/−58 bits in Group A to 11,138+/−705 bits in Group B. The night/day records observed in Group A (200/800 bits) were drastically increased in Group B (1000–4000/4000–14,000 bits) and variable along seasons. A very high correlation was observed between fly density and visual records or pedometer records (PR). Two-hour PRs proved to be a reliable predictive tool for fly density. Moreover, the pedometers revealed an unsuspected but significant nuisance of mosquitoes, which should be thoroughly investigated. [ABSTRACT FROM AUTHOR]

Deep learning-based automated segmentation of vascular structures in preoperative CT angiography (CTA) images contributes to computer-assisted diagnosis and interventions. While CTA is the common standard, non-contrast CT imaging has the advantage of avoiding complications associated with contrast agents. However, the challenges of labor-intensive labeling and high labeling variability due to the ambiguity of vascular boundaries hinder conventional strong-label-based, fully-supervised learning in non-contrast CTs. This paper introduces a novel weakly-supervised framework using the elliptical topology nature of vascular structures in CT slices. It includes an efficient annotation process based on our proposed standards, an approach of generating 2D Gaussian heatmaps serving as pseudo labels, and a training process through a combination of voxel reconstruction loss and distribution loss with the pseudo labels. We assess the effectiveness of the proposed method on one local and two public datasets comprising non-contrast CT scans, particularly focusing on the abdominal aorta. On the local dataset, our weakly-supervised learning approach based on pseudo labels outperforms strong-label-based fully-supervised learning (1.54% of Dice score on average), reducing labeling time by around 82.0%. The efficiency in generating pseudo labels allows the inclusion of label-agnostic external data in the training set, leading to an additional improvement in performance (2.74% of Dice score on average) with a reduction of 66.3% labeling time, where the labeling time remains considerably less than that of strong labels. On the public dataset, the pseudo labels achieve an overall improvement of 1.95% in Dice score for 2D models with a reduction of 68% of the Hausdorff distance for 3D model. • Reducing labor-intensive labeling while enhancing vascular structure segmentation quality. • Presenting a flexible weakly-supervised method for diverse 2D/3D DL models in non-contrast CTs. • Developing annotation standards that cut labeling time by 82 • Proposing a pseudo-label generation method with novel loss functions over standard segmentation losses. [ABSTRACT FROM AUTHOR]

PP/EPDM Thermoplastic Vulcanizate (TPV) filled with carbon black (CB) has been prepared and the localization of the filler in the blend was observed to be dependent on the crosslinking chemistry: in the rubber phase when the EPDM was crosslinked with phenolic resin (resol) and at the interface when the EPDM was crosslinked with dicumyl peroxide (DCP). It was proved, based on model reactions that mimicked what could happen during the process at high temperature, that DCP led to polymer chains grafting at the surface of the CB. This phenomenon was additional to the classical EPDM crosslinking and PP β-scission reactions. These reactions involved a modification of the interfacial tensions within this ternary blend, and explained preferentially the carbon black localization at the interface between the PP and the EPDM. • The carbon black is in the EPDM phase when resol is used. • The carbon black is at the interface when peroxide is used. • Polymer chains are grafted on CB surface when peroxide is used. [ABSTRACT FROM AUTHOR]

In this work we propose a generic modeling approach for simulating percutaneous transluminal angioplasty (PTA) endovascular treatment, and evaluating the influence of balloon design, plaque composition, and balloon sizing on acute post‐procedural outcomes right after PTA, without stent implantation. Clinically‐used PTA balloons were classified into two categories according to their compliance characteristics, and were modeled correspondingly. Self‐defined elastoplastic constitutive laws were implemented within the plaque and artery models, after calibration based on experimental and clinical data. Finite element method (FEM) implicit solver was used to simulate balloon inflation and deflation. Besides balloon profile at max inflation, results are mainly assessed in terms of the elastic recoil ratio (ERR) and lumen gain ratio (LGR) obtained immediately after PTA. No variations in ERR nor LGR values were detected when the balloon design changed, despite the differences observed in their profile at max inflation. Moreover, LGR and ERR inversely varied with the augmentation of calcification level within the plaque (−11% vs. +4% respectively, from fully lipidic to fully calcified plaque). Furthermore, results showed a direct correlation between balloon sizing and LGR and ERR, with noticeably higher rates of change for LGR (+18% and +2% for LGR and ERR respectively for a calcified plaque and a balloon pressure increasing from 10 to 14 atm). However a larger LGR comes with a higher risk of arterial rupture. This proposed methodology opens the way for evaluation of angioplasty balloon selections towards clinical procedure optimization. [ABSTRACT FROM AUTHOR]

Understanding what controls the travelling distance of large landslides has been the topic of considerable debate. By combining observation and experimental data with depth-averaged continuum modelling of landslides and generated seismic waves, it was empirically observed that lower effective friction had to be taken into account in the models to reproduce the dynamics and runout distance of larger volume landslides. Moreover, such simulation and observation results are compatible with a friction weakening with velocity as observed in earthquake mechanics. We investigate here as to whether similar empirical reduced friction should be put into discrete element models (DEM) to reproduce observed runout of large landslides on Earth and on Mars. First we show that, in the investigated parameter range and for a given volume, the runout distance simulated by 3D DEM is not much affected by the number (i.e. size) of grains once this number attains ~ 8000. We then calibrate the model on laboratory experiments and simulate other experiments of granular flows on inclined planes, making it possible for the first time to reproduce the observed effect of initial volume and aspect ratio on runout distances. In particular, the normalised runout distance starts to depend on the volume involved only above a critical slope angle > 16–19°, as observed experimentally. Finally, based on field data (volume, topography, deposit), we simulate a series of landslides on simplified inclined topography. The empirical friction coefficient, calibrated to reproduce the observed runout for each landslide, is shown to decrease with increasing landslide volume (or velocity), going down to values as low as 0.1–0.2. No distinguishable difference is observed between the behaviour of terrestrial and Martian landslides. [ABSTRACT FROM AUTHOR]

When the Hale impact crater penetrated the martian cryosphere 1Ga, landforms indicating post-impact volatile mobilisation were generated. We have found landforms in the ejecta blanket of Hale Crater similar to 'permafrost molards' found in periglacial environments on Earth, and probably related to the past or present presence of volatiles at/near the surface. Permafrost molards are conical mounds of debris associated with landslide deposits, resulting from the degradation of blocks of ice-rich material mobilised by a landslide in periglacial terrains. Here we analyse the spatial and topographic distribution of conical mounds around the Hale crater at regional and local scales, and compare them to those of molards on the deposits of the Mount Meager debris avalanche in Canada. Hale Crater's conical mounds are located at the distal boundary of the thickest ejecta blanket, which is the closest to the main crater. We observe a similar spatial arrangement of molards along the distal parts of the terminal lobe of the Mount Meager debris avalanche. We then compare the morphology and morphometrics of the conical mounds on Hale Crater to those of terrestrial molards on the Paatuut and Niiortuut rock avalanches in western Greenland. We find that morphology and setting of conical mounds within Hale Crater ejecta are consistent with the formation pathway of molards on Earth. We infer that they originated from blocks of ice-cemented regolith that were produced by the Hale-crater-forming impact, transported by the ejecta flows, and finally degraded to cones of debris (molards) on loss of the interstitial ice. The similarities in distribution between the ejecta flows of Hale and Mount Meager debris avalanche on Earth suggest that the mounds resulted from the rheological separation of the ejecta flows, with a relatively fluid-poor phase that allowed the volatile-rich blocks to survive transport. This supports the prevailing hypothesis that the Hale impact event penetrated the martian cryosphere, providing important constraints on the rheology of martian ejecta deposits. • Conical mounds reveal the history of the cryosphere near the Argyre impact basin. • Conical mounds within the ejecta of Hale Crater are similar to terrestrial molards. • Spatial distribution and morphometry of terrestrial and martian molards are compared. • Conical mounds in Hale reveal volatile-rich ejecta at the time of emplacement. [ABSTRACT FROM AUTHOR]

Wind-blown dunes are a record of the climatic history in Titan’s equatorial region. Through modeling of the climatic conditions associated with Titan’s historical orbital configurations (arising from apsidal precessions of Saturn’s orbit), we present evidence that the orientations of the dunes are influenced by orbital forcing. Analysis of 3 Titan general circulation models (GCMs) in conjunction with a sediment transport model provides the first direct intercomparison of results from different Titan GCMs. We report variability in the dune orientations predicted for different orbital epochs of up to 70°. Although the response of the GCMs to orbital forcing varies, the orbital influence on the dune orientations is found to be significant across all models. Furthermore, there is near agreement among the two models run with surface topography, with 3 out of the 5 dune fields matching observation for the most recent orbital cycle. Through comparison with observations by Cassini, we find situations in which the observed dune orientations are in best agreement with those modeled for previous orbital configurations or combinations thereof, representing a larger portion of the cycle. We conclude that orbital forcing could be an important factor in governing the present-day dune orientations observed on Titan and should be considered when modeling dune evolution. [ABSTRACT FROM AUTHOR]

Dunes cover about 15 % of Titan’s visible surface, and represent one of the largest reservoirs of hydrocarbon solids on Titan (Rodriguez, S. et al. [2014]. Icarus 230, 168–179; Lopes, R.M.C. et al. [2016]. Icarus 270, 162–182.). Herein, we use data from the Cassini spacecraft to derive constraints on the compositional and regional variability of Titan’s dune and interdune regions by combining spectral information from the Visual and Infrared Mapping Spectrometer (VIMS) and spatial information from Synthetic Aperture RADAR (SAR) data. Using the combined datasets, we extract pure infrared spectra of dune and interdune regions by extrapolating linear correlations between VIMS reflectance and dune area fraction calculated in each VIMS footprint from SAR images. We applied the same method using the Cassini RADAR Radiometer dataset to extract the microwave surface emissivity of the dune and interdune regions. Globally the dune spectra show little variation, but we find that the interdune spectra exhibit several different behaviors. Similarly, we extract from passive radiometry a mean dune emissivity of 0.98 ± 0.01, while interdune emissivity varies from 0.86 to 0.98. We find that the interdune regions are often spectrally similar to other Titan terrain units, namely Caladan Planitia, the Adiri Mountains, and Sinlap crater, while the dunes are spectrally distinct from all terrain units. Around Sinlap crater, the interdune regions correspond to the dark blue VIMS unit: the dunes could be forming on top of the ejecta, or the material corresponding to the blue unit could be depositing preferentially in the interdunes areas. There was one region in the Belet sand sea where we were unable to extract the dune and interdune spectra and emissivities in spite of high-quality data, which we interpret to result from a thick sand cover in the interdune regions, implying inactive or saturated dune fields. However, the fact that we were able to extract distinct dune and interdune spectra and emissivities in most of Titan’s dune fields makes a strong case for sand-free interdune areas of varying composition in these regions, on depths from micrometers to decimeters. This would imply that the sand dunes have been active recently on geologic timescales. [ABSTRACT FROM AUTHOR]

Highlights: [•] Presents a map of Titan Seas with volume estimate. [•] Notes strong flow in constriction (‘throat’) between Kraken basins. [•] Evaluates tidal dissipation. [•] Determines mixing timescales between these basins. [Copyright &y& Elsevier]

Highlights: [•] Presents a global topographic map of Titan. [•] Discovers southern basins and several highlands. [•] Splines used to extend ∼11% data coverage to global map. [•] Enables correlation studies and modeling. [ABSTRACT FROM AUTHOR]

Abstract: During endovascular aortic aneurysm repair (EVAR), the introduction of medical devices deforms the arteries. The aim of the present study was to assess the feasibility of finite element simulation to predict arterial deformations during EVAR. The aortoiliac structure was extracted from the preoperative CT angiography of fourteen patients underwent EVAR. The simulation consists in modeling the deformation induced by the stiff wire used during EVAR. The results of the simulation were projected onto the intraoperative images, using a 3D/2D registration. The mean distance between the real and simulated guidewire was 2.3±1.1mm. Our results demonstrate that finite element simulation is feasible and appear to be reproducible in modeling device/tissue interactions and quantifying anatomic deformations during EVAR. [Copyright &y& Elsevier]

Abstract: Gullies on terrestrial sand dunes are rare, and their presence on Mars, as well as their mechanical properties, and the quantity of fluid required for their formations currently remain poorly understood. This study focuses on gully morphologies on the Russell megadune (54.5°S; 12.7°E) using High Resolution Imaging Science Experiment (HiRISE) images and Digital Terrain Models (DTM). Based on the scenario of ground ice melting in a periglacial environment, we propose to test the hypothesis that Martian gullies on dunes are debris flows. This implies a flow with a significant proportion of liquid water (>10% in volume). We used an original method to study Martian gullies based on empirical equations from terrestrial debris flows in order to calculate the physical properties of Martians flows. We observe a decrease in viscosity induced by the relative increase of fluid concentration (from 28% to 39%) during the flow advance. The total estimated volume of eroded and deposited material range from ∼14850m3 to ∼18890m3. The volume of liquid water required to generate one gully ranges from 4450m3 to 6900m3. The calculated results for Martian gullies are consistent with terrestrial studies on debris flows. Based on a morphological description and on the estimated physical parameters, we propose a model for gully formation on Martian dunes. The melt water from near-surface ground ice is incorporated in the debris flow and water concentration increases during its propagation. The increase of water concentration in the debris flow can be explained by a progressive increase of water/ice content in the permafrost downstream. Consequently, the lack of a final deposit at the front of the gullies tends to demonstrate that the flow became relatively highly concentrated in liquid downstream and all the water could have been lost in the final stage of the flow. This process could explain the lack of terminal lobes at the front of the gullies. We conclude that a process of formation similar to terrestrial debris flows is plausible. The large amount of liquid water involved requires formation of Martian gullies on dunes during a warmer climatic episode. [Copyright &y& Elsevier]

Abstract: This work deals with the treatment planning optimization for intravascular brachytherapy (IVB) in peripheral arteries. The objective is both to quantitatively study the validity of different hypotheses required for a reliable application of the treatment with current techniques, and to contribute to the definition and the specification of a new optimized procedure taking into account the actual patient''s vessel geometry. The detection of vascular luminal surface was performed by an image analysis process, i.e., virtual active navigation, applied to standard CT data. Dose distribution was calculated according to the formalism proposed and recommended by the AAPM in TG43 and TG60. A method combining simulated annealing and BFGS algorithms was applied to optimize the parameters associated with the dwell points such as their number, positions, and dwell times. Dose-surface histogram (DSH) was used to evaluate the dose distribution results. Four levels of accuracy in target surface description were tested. The application of this optimization method to four different CT data sets including patient data, phantom and animal models showed that the treatment plan can be improved when the actual vessel geometry has been taken into account. [Copyright &y& Elsevier]

Messenger RNAs that do not contain a long open reading frame (ORF) or non-protein-coding RNAs (npcRNAs) are an emerging novel class of transcripts. Their functions may involve the RNA molecule itself and/or short ORF-encoded peptides. npcRNA genes are difficult to identify using standard gene prediction programs that rely on the presence of relatively long ORFs. Here, we used detailed bioinformatic analyses of expressed sequence tag/cDNA databases to detect a restricted set of npcRNAs in the Arabidopsis (Arabidopsis thaliana) genome and further characterized these transcripts using a combination of bioinformatic and molecular approaches. Compositional analyses revealed strong nucleotide strand asymmetries in the npcRNAs, as well as a biased GC content, suggesting the existence of functional constraints on these RNAs. Thirteen of these transcripts display tissue-specific expression patterns, and three are regulated in conditions affecting root architecture. The npcRNA 78 gene contains the miR162 sequence in an alternative intron and corresponds to the MIR162a locus. Although DICER-LIKE 1 (DCL1) mRNA is known to be regulated by miR162-guided cleavage, its level does not change in a mir162a mutant. Alternative splicing of npcRNA 78 leads to several transcript isoforms, which all accumulate in a dcl1 mutant. This suggests that npcRNA 78 is a genuine substrate of DCL1 and that splicing of this microRNA primary transcript and miR162 processing are competitive nuclear events. Our results provide new insights into Arabidopsis npcRNA biology and the potential roles of these genes. [ABSTRACT FROM AUTHOR]

InSight landed on Mars on November 26, 2018, in western Elysium Planitia. The Mars crust beneath the lander is subject to complex geologic history next to the great topographic and crustal dichotomy of Mars. Understanding this part of the Martian crust in the subsurface would aid future investigations of the internal structure of the planet based on seismic datasets collected by the Seismic Experiment for Interior Structure (SEIS) instrument. Here, we investigate the subsurface structure and composition from the analysis of mineralogy and morphology of exposures in impact craters as well as on scarps and knobs in the general region of Elysium Planitia. Using a combination of orbital datasets, we identify exposures of subsurface materials with distinct composition and physical properties. We find olivine and pyroxene detections associated with small impact craters (1.5–7 km) rim in the vicinity of InSight lander, as well as in the transition unit and Elysium volcanic unit. Fe/Mg phyllosilicates have been identified in the central peak of the 51-km diameter Kalpin crater and on knobs in the transition unit between the dichotomy and the plains. In addition, eroded meter-scale layered unit subject to erosion has been identified in six impact craters to the north-east of the landing site, including Kalpin crater. Massive bedrock and layered, weak materials co-occur in the transition unit, indicating a complex origin. These results together suggest both materials with altered composition and layered deposit occur as distinct geologic units beneath the basaltic lava flow units. Through analogy with terrestrial sedimentary rocks or clay-bearing sediments, we suggest physically weak materials exist beneath the lava flow units in the general region of Elysium Planitia. The spatial distribution and continuity of these materials are unclear due to the lack of exposures within the lava flow unit where the InSight lander is located. These subsurface materials of distinct physical properties may result in increased attenuation or reverberations of seismic waves, to be collected by SEIS. The findings suggest a close investigation of the potential effects of subsurface stratigraphy on seismic data would help inform future data interpretation and understanding of the internal structure of Mars. • Kalpin crater north of the InSight landing site exposes a phyllosilicate-bearing unit beneath the lava flows. • Layered, yardang-forming materials near the landing site indicate extended sedimentary unit in the subsurface. • Heterogeneous composition and structure with possible weak layers could affect the seismic signal acquired by InSight. [ABSTRACT FROM AUTHOR]

In addition to blood pathogen transmission, insects of the order Diptera affect livestock through visual and contact harassment; blood-feeders are responsible for painful bites and blood despoliation, generating behavioral modifications, anemia, and production losses. Knowledge of their economic impact is a basis for cost-effective control. Here, we measured the global impact of diptera insects by comparing two batches of six feeder cattle, one in the open air and the other protected by a mosquito net. The analytical data were insect density in the open air and, for feeder cattle, tail flick counts, hematocrit values (Ht), feed intake, feed conversion ratio (FCR), and live body weight gain (LBWG). Over a period of five months, the results showed significant losses in the LBWG of cattle exposed to insects, estimated at 8.0 ± 1.5 kg/month [2.7; 13.3], with a total loss reaching 40.0 ± 5.5 kg/head. Main diurnal insects were Stomoxys spp. and Musca crassirostris . There was a strong correlation between fly density and diurnal tail flicks. Night trapping and tail flicks showed a potentially important role of mosquitoes to be further explored. The Ht levels of exposed animals were 3-4% lower than those of controls. FCRs indicated that exposed animals needed 33% more dry matter intake/kg of LBWG. An economic assessment showed that dipterans were responsible for a 10-11% loss in LBWG during the main growing period of feeder cattle (10-15 months). A feedlot of 100 calves would register a total loss of USD 16,000 within 5 months, which appears to be an unexpectedly huge loss caused by dipterans. Investing part of this money into fly control would probably be beneficial.

Climate change is increasingly predisposing polar regions to large landslides. Tsunamigenic landslides have occurred recently in Greenland ( Kalaallit Nunaat ), but none have been reported from the eastern fjords. In September 2023, we detected the start of a 9-day-long, global 10.88-millihertz (92-second) monochromatic very-long-period (VLP) seismic signal, originating from East Greenland. In this study, we demonstrate how this event started with a glacial thinning-induced rock-ice avalanche of 25 × 10 6 cubic meters plunging into Dickson Fjord, triggering a 200-meter-high tsunami. Simulations show that the tsunami stabilized into a 7-meter-high long-duration seiche with a frequency (11.45 millihertz) and slow amplitude decay that were nearly identical to the seismic signal. An oscillating, fjord-transverse single force with a maximum amplitude of 5 × 10 11 newtons reproduced the seismic amplitudes and their radiation pattern relative to the fjord, demonstrating how a seiche directly caused the 9-day-long seismic signal. Our findings highlight how climate change is causing cascading, hazardous feedbacks between the cryosphere, hydrosphere, and lithosphere.

Purpose: Segmentation of vascular structures in preoperative computed tomography (CT) is a preliminary step for computer-assisted endovascular navigation. It is a challenging issue when contrast medium enhancement is reduced or impossible, as in the case of endovascular abdominal aneurysm repair for patients with severe renal impairment. In non-contrast-enhanced CTs, the segmentation tasks are currently hampered by the problems of low contrast, similar topological form, and size imbalance. To tackle these problems, we propose a novel fully automatic approach based on convolutional neural network., Approach: The proposed method is implemented by fusing the features from different dimensions by three kinds of mechanisms, i.e., channel concatenation, dense connection, and spatial interpolation. The fusion mechanisms are regarded as the enhancement of features in non-contrast CTs where the boundary of aorta is ambiguous., Results: All of the networks are validated by three-fold cross-validation on our dataset of non-contrast CTs, which contains 5749 slices in total from 30 individual patients. Our methods achieve a Dice score of 88.7% as the overall performance, which is better than the results reported in the related works., Conclusions: The analysis indicates that our methods yield a competitive performance by overcoming the above-mentioned problems in most general cases. Further, experiments on our non-contrast CTs demonstrate the superiority of the proposed methods, especially in low-contrast, similar-shaped, and extreme-sized cases., (© 2023 Society of Photo-Optical Instrumentation Engineers (SPIE).)

Purpose: Endovascular revascularization is becoming the established first-line treatment of peripheral artery disease (PAD). Ultrasound (US) imaging is used pre-operatively to make the first diagnosis and is often followed by a CT angiography (CTA). US provides a non-invasive and non-ionizing method for the visualization of arteries and lesion(s). This paper proposes to generate a 3D stretched reconstruction of the femoral artery from a sequence of 2D US B-mode frames., Methods: The proposed method is solely image-based. A Mask-RCNN is used to segment the femoral artery on the 2D US frames. In-plane registration is achieved by aligning the artery segmentation masks. Subsequently, a convolutional neural network (CNN) predicts the out-of-plane translation. After processing all input frames and re-sampling the volume according to the vessel's centerline, the whole femoral artery can be visualized on a single slice of the resulting stretched view., Results: 111 tracked US sequences of the left or right femoral arteries have been acquired on 18 healthy volunteers. fivefold cross-validation was used to validate our method and achieve an absolute mean error of 0.28 ± 0.28 mm and a median drift error of 8.98%., Conclusion: This study demonstrates the feasibility of freehand US stretched reconstruction following a deep learning strategy for imaging the femoral artery. Stretched views are generated and can give rich diagnosis information in the pre-operative planning of PAD procedures. This visualization could replace traditional 3D imaging in the pre-operative planning process, and during the pre-operative diagnosis phase, to identify, locate, and size stenosis/thrombosis lesions., (© 2022. CARS.)

Background: Fusion imaging makes it possible to improve endovascular procedures and is mainly used in hybrid rooms for aortic procedures. The objective of this study was to evaluate the feasibility of fusion imaging for femoropopliteal endovascular procedures with a mobile flat plane sensor and dedicated software to assist endovascular navigation., Materials and Methods: Between May and December 2017, 41 patients requiring femoropopliteal endovascular revascularization were included. Interventions were carried out in a conventional surgical room equipped with a mobile plane sensor (Cios Alpha, Siemens). The numerical video stream was transmitted to an angionavigation station (EndoNaut (EN), Therenva). The software created an osseous and arterial panorama of the treated limb from the angiographies carried out at the beginning of procedure. After each displacement of the table, the software relocated the current image on the osseous panorama, with 2D-2D resetting, and amalgamated the mask of the arterial panorama. The success rates of creation of osseous and arterial panorama and the success of relocation were evaluated. The data concerning irradiation, the volume of contrast (VC) injected, and operative times were recorded., Results: Osseous panoramas could be automatically generated for the 41 procedures, without manual adjustment in 33 cases (80.5%). About 35 relocations based on a 2D-2D resetting could be obtained in the 41 procedures, with a success rate of 85%. The causes of failure were a change in table height or arch angulation. The average duration of intervention was 74.5 min. The irradiation parameters were duration of fluoroscopy 17.8 ± 13.1 min, air kerma 80.5 ± 68.4 mGy, and dose area product 2140 ± 1599 μGy m 2 . The average VC was 24.5 ± 14 mL., Conclusions: This preliminary study showed that fusion imaging is possible in a nonhybrid room for peripheral procedures. Imagery of mobile C-arms can be improved for femoropopliteal endovascular procedures without heavy equipment. These imagery tools bring an operative comfort and could probably reduce irradiation and the injected VC. The clinical benefit must be evaluated in more patients in a randomized comparative study with a rigorous methodology., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: During endovascular aneurysm repair (EVAR), complex iliac anatomy is a source of complications such as unintentional coverage of the hypogastric artery. The aim of our study was to evaluate ability to predict coverage of the hypogastric artery using a biomechanical model simulating arterial deformations caused by the delivery system., Methods: The biomechanical model of deformation has been validated by many publications. The simulations were performed on 38 patients included retrospectively, for a total of 75 iliac arteries used for the study. On the basis of objective measurements, two groups were formed: one with "complex" iliac anatomy (n = 38 iliac arteries) and the other with "simple" iliac anatomy (n = 37 iliac arteries). The simulation enabled measurement of the lengths of the aorta and the iliac arteries once deformed by the device. Coverage of the hypogastric artery was predicted if the deformed renal/iliac bifurcation length (L pre ) was less than the length of the implanted device (L stent -measured on the postoperative computed tomography [CT]) and nondeformed L pre was greater than L stent ., Results: Nine (12%) internal iliac arteries were covered unintentionally. Of the coverage attributed to perioperative deformations, 1 case (1.3%) occurred with simple anatomy and 6 (8.0%) with complex anatomy (P = 0.25). All cases of unintentional coverage were predicted by the simulation. The simulation predicted hypogastric coverage in 35 cases (46.7%). There were therefore 26 (34.6%) false positives. The simulation had a sensitivity of 100% and a specificity of 60.6%. On multivariate analysis, the factors significantly predictive of coverage were the iliac tortuosity index (P = 0.02) and the predicted margin between the termination of the graft limb and the origin of the hypogastric artery in nondeformed (P = 0.009) and deformed (P = 0.001) anatomy., Conclusions: Numerical simulation is a sensitive tool for predicting the risk of hypogastric coverage during EVAR and allows more precise preoperative sizing. Its specificity is liable to be improved by using a larger cohort., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Fusion imaging is a technique that facilitates endovascular navigation but is only available in hybrid rooms. The goal of this study was to evaluate the feasibility of fusion imaging with a mobile C-arm in a conventional operating room through the use of an angionavigation station., Methods: From May 2016 to June 2017, the study included all patients who underwent an aortic stent graft procedure in a conventional operating room with a mobile flat-panel detector (Cios Alpha, Siemens) connected to an angionavigation station (EndoNaut, Therenva). The intention was to perform preoperative 3D computerized tomography/perioperative 2D fluoroscopy fusion imaging using an automatic registration process. Registration was considered successful when the software was able to correctly overlay preoperative 3D vascular structures onto the fluoroscopy image. For EVAR, contrast dose, operation time, and fluoroscopy time (FT) were compared with those of a control group drawn from the department's database who underwent a procedure with a C-arm image intensifier., Results: The study included 54 patients, and the procedures performed were 49 EVAR, 2 TEVAR, 2 IBD, and 1 FEVAR. Of the 178 registrations that were initialized, it was possible to use the fusion imaging in 170 cases, that is, a 95.5% success rate. In the EVAR comparison, there were no difference with the control group (n = 103) for FT (21.9 ± 12 vs. 19.5 ± 13 min; P = 0.27), but less contrast agent was used in the group undergoing a procedure with the angionavigation station (42.3 ± 22 mL vs. 81.2 ± 48 mL; P < 0.001), and operation time was shorter (114 ± 44 vs. 140.8 ± 38 min; P < 0.0001)., Conclusions: Fusion imaging is feasible with a mobile C-arm in a conventional operating room and thus represents an alternative to hybrid rooms. Its clinical benefits should be evaluated in a randomized series, but our study already suggests that EVAR procedures might be facilitated with an angionavigation system., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Purpose: Interventional endovascular treatment has become the first line of management in the treatment of peripheral artery disease (PAD). However, contrast and radiation exposure continue to limit the feasibility of these procedures. This paper presents a novel hybrid image fusion system for endovascular intervention of PAD. We present two different roadmapping methods from intra- and pre-interventional imaging that can be used either simultaneously or independently, constituting the navigation system., Methods: The navigation system is decomposed into several steps that can be entirely integrated within the procedure workflow without modifying it to benefit from the roadmapping. First, a 2D panorama of the entire peripheral artery system is automatically created based on a sequence of stepping fluoroscopic images acquired during the intra-interventional diagnosis phase. During the interventional phase, the live image can be synchronized on the panorama to form the basis of the image fusion system. Two types of augmented information are then integrated. First, an angiography panorama is proposed to avoid contrast media re-injection. Information exploiting the pre-interventional computed tomography angiography (CTA) is also brought to the surgeon by means of semiautomatic 3D/2D registration on the 2D panorama. Each step of the workflow was independently validated., Results: Experiments for both the 2D panorama creation and the synchronization processes showed very accurate results (errors of 1.24 and [Formula: see text] mm, respectively), similarly to the registration on the 3D CTA (errors of [Formula: see text] mm), with minimal user interaction and very low computation time. First results of an on-going clinical study highlighted its major clinical added value on intraoperative parameters., Conclusion: No image fusion system has been proposed yet for endovascular procedures of PAD in lower extremities. More globally, such a navigation system, combining image fusion from different 2D and 3D image sources, is novel in the field of endovascular procedures.

Purpose: Abdominal aortic aneurysm (AAA) is a localized, permanent and irreversible enlargement of the artery, with the formation of thrombus into the inner wall of the aneurysm. A precise patient-specific segmentation of the thrombus is useful for both the pre-operative planning to estimate the rupture risk, and for post-operative assessment to monitor the disease evolution. This paper presents a generic approach for 3D segmentation of thrombus from patients suffering from AAA using computed tomography angiography (CTA) scans., Methods: A fast and versatile thrombus segmentation approach has been developed. It is composed of initial centerline detection and aorta lumen segmentation, an optimized pre-processing stage and the use of a 3D deformable model. The approach has been designed to be very generic and requires minimal user interaction. The proposed method was tested on different datasets with 145 patients overall, including pre- and post-operative CTAs, abdominal aorta and iliac artery sections, different calcification degrees, aneurysm sizes and contrast enhancement qualities., Results: The thrombus segmentation approach showed very accurate results with respect to manual delineations for all datasets ([Formula: see text] and [Formula: see text] for abdominal aorta sections on pre-operative CTA, iliac artery sections on pre-operative CTAs and aorta sections on post-operative CTA, respectively). Experiments on the different patient and image conditions showed that the method was highly versatile, with no significant differences in term of precision. Comparison with the level-set algorithm also demonstrated the superiority of the 3D deformable model. Average processing time was [Formula: see text]., Conclusion: We presented a near-automatic and generic thrombus segmentation algorithm applicable to a large variability of patient and imaging conditions. When integrated in an endovascular planning system, our segmentation algorithm shows its compatibility with clinical routine and could be used for pre-operative planning and post-operative assessment of endovascular procedures.

Background: The evolution and correlation between the aortic neck and distally located iliac necks after endovascular treatment of abdominal aortic aneurysms (AAAs) was studied., Methods: Of 179 patients who had undergone AAA repair between 2003 and 2007, 61 received the same radiologic follow-up and were included in this retrospective study. Data for 61 aortic necks and 115 iliac arteries were analyzed using the preoperative scan, 1-month visit, and final follow-up, with a minimum mean follow-up of 24 ± 15.2 months. Three measurements were taken of the aortic neck: subrenal (D1a), 15 mm below the lowest renal artery (D1b), and at the origin of the aneurysm (D1c). Three measurements were taken at the level of the iliac arteries: origin (Da), middle (Db), and the iliac bifurcation (Dc). These measurements were analyzed using analysis of variance and Spearman correlation coefficient. The results were evaluated for subsequent endoleaks, migrations, and reinterventions. All diameters were compared between patients with a regression of >10% in the greatest diameter of AAA at last follow-up (group A, n = 35) and those without (group B, n = 26)., Results: All diameters (in mm) increased significantly over time at the level of the proximal neck (D1a = 3.7 ± 2.8, P = .018; D1b = 4.4 ± 2.5, P = .016; D1c = 4.3 ± 3.1, P = .036) and iliac arteries (Da = 2.1 ± 0.2, P = .0006; Db = 2.5 ± 0.5, P = .0006; Dc = 3 ± 0.7, P = .007). The increase in diameters at the proximal neck and iliac arteries evolved independently (insignificant correlation), with the exception of D1b and Dc (P = .006), which showed a weak correlation (r = 0.363). The group A patients presented increases in all diameters, although to a less significant extent (P < .05) than group B patients. During follow-up, a proximal endoleak and a distal endoleak occurred, both requiring reintervention., Conclusions: Our results show a trend toward dilatation of the aortic neck and iliac arteries, with no correlation between the two levels, even in patients with a regression of the aneurysm sac during follow-up. Although this study found no correlation with the occurrence of endoleaks, our results suggest the need for a longer follow-up, especially on the landing sites., (Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Long non-protein coding RNAs (npcRNA) represent an emerging class of riboregulators, which either act directly in this long form or are processed to shorter miRNA and siRNA. Genome-wide bioinformatic analysis of full-length cDNA databases identified 76 Arabidopsis npcRNAs. Fourteen npcRNAs were antisense to protein-coding mRNAs, suggesting cis-regulatory roles. Numerous 24-nt siRNA matched to five different npcRNAs, suggesting that these npcRNAs are precursors of this type of siRNA. Expression analyses of the 76 npcRNAs identified a novel npcRNA that accumulates in a dcl1 mutant but does not appear to produce trans-acting siRNA or miRNA. Additionally, another npcRNA was the precursor of miR869 and shown to be up-regulated in dcl4 but not in dcl1 mutants, indicative of a young miRNA gene. Abiotic stress altered the accumulation of 22 npcRNAs among the 76, a fraction significantly higher than that observed for the RNA binding protein-coding fraction of the transcriptome. Overexpression analyses in Arabidopsis identified two npcRNAs as regulators of root growth during salt stress and leaf morphology, respectively. Hence, together with small RNAs, long npcRNAs encompass a sensitive component of the transcriptome that have diverse roles during growth and differentiation.

A two-step method to determine the seed parameters for the planning of peripheral intravascular brachytherapy, which took the actual vessel geometry into consideration, was developed. Firstly, the characteristics of the vessel geometry was obtained by using active navigation; Then a method combined genetic algorithm with BFGS algorithm was applied to optimize the number of seeds, and the parameters associated with each seed such as the position, and the dwell time. Application of the method to a phantom model and three animal models of stenosis shows that promising result could be obtained, and the planning of peripheral intravascular brachytherapy should take actual vessel geometry into consideration.