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The modeling of atmospheric processes in the context of weather and climate simulations is an important and computationally expensive challenge. The temporal integration of the underlying PDEs requires a very large number of time steps, even when the terms accounting for the propagation of fast atmospheric waves are treated implicitly. Therefore, the use of parallel-in-time integration schemes to reduce the time-to-solution is of increasing interest, particularly in the numerical weather forecasting field. We present a multi-level parallel-in-time integration method combining the Parallel Full Approximation Scheme in Space and Time (PFASST) with a spatial discretization based on Spherical Harmonics (SH). The iterative algorithm computes multiple time steps concurrently by interweaving parallel high-order fine corrections and serial corrections performed on a coarsened problem. To do that, we design a methodology relying on the spectral basis of the SH to coarsen and interpolate the problem in space. The methods are evaluated on the shallow-water equations on the sphere using a set of tests commonly used in the atmospheric flow community. We assess the convergence of PFASST-SH upon refinement in time. We also investigate the impact of the coarsening strategy on the accuracy of the scheme, and specifically on its ability to capture the high-frequency modes accumulating in the solution. Finally, we study the computational cost of PFASST-SH to demonstrate that our scheme resolves the main features of the solution multiple times faster than the serial schemes.

The modeling of atmospheric processes in the context of weather and climate simulations is an important and computationally expensive challenge. The temporal integration of the underlying PDEs requires a very large number of time steps, even when the terms accounting for the propagation of fast atmospheric waves are treated implicitly. Therefore, the use of parallel-in-time integration schemes to reduce the time-to-solution is of increasing interest, particularly in the numerical weather forecasting field. We present a multi-level parallel-in-time integration method combining the Parallel Full Approximation Scheme in Space and Time (PFASST) with a spatial discretization based on Spherical Harmonics (SH). The iterative algorithm computes multiple time steps concurrently by interweaving parallel high-order fine corrections and serial corrections performed on a coarsened problem. To do that, we design a methodology relying on the spectral basis of the SH to coarsen and interpolate the problem in space. The methods are evaluated on the shallow-water equations on the sphere using a set of tests commonly used in the atmospheric flow community. We assess the convergence of PFASST-SH upon refinement in time. We also investigate the impact of the coarsening strategy on the accuracy of the scheme, and specifically on its ability to capture the high-frequency modes accumulating in the solution. Finally, we study the computational cost of PFASST-SH to demonstrate that our scheme resolves the main features of the solution multiple times faster than the serial schemes.

The Yacoraite Formation is a complex lacustrine microbialite-bearing carbonate formation whose heterogeneity is due to different sedimentary facies associations and several microbialite geobodies. The bi-variate plurigaussian geostatistical method is applied to simulate in parallel these two types of heterogeneity in a 3D reservoir-scale geological model. Each variable is simulated by a complete plurigaussian method based on geological interpretation and field observations and quantifications. They are coupled through the occurrence of the microbialites within the sedimentary facies and associated into combined facies giving a one-glance representation of the reservoir heterogeneity, then used to constrain the porosity simulation.

Abstract Background Epithelial ingrowth is a rare complication after ocular perforation and can become manifest many years after the primary trauma. Case presentation A 49-year-old patient presented with a positive Seidel test of unclear origin at her left eye, as well as a sharply defined anterior-stromal corneal scar at both eyes. Prior operations included a bilateral laser-assisted blepharoplasty 3 months earlier. The patient indicated to have been on holiday to France 5 months earlier, during an ongoing oak processionary moth caterpillars infestation. The examination using confocal microscopy confirmed a corneal perforation at the left eye and revealed corneal epithelial ingrowth capped with scarred stroma in both eyes. We performed a penetrating keratoplasty at the left eye. The scarred and perforated host cornea was divided into 4 pieces for further investigation: microbiology (negative), virology (negative), histology and transmission electron microscopy (TEM). Histology revealed differently structured epithelium, centrally inverted into the stroma through defects in Bowman’s layer. TEM revealed full thickness corneal perforation with an epithelial plug extending to the lower third of the cornea, but without evidence of epithelial cell migration into the anterior chamber. Our differential diagnosis of the unclear positive Seidel test with epithelial ingrowth was as follows: (1) corneal perforation by hairs of the oak processionary moth caterpillar, although no hairs could be found histologically; (2) corneal perforation during laser-assisted blepharoplasty, which may be supported by the presence of pigmented cells on the posterior surface of Descemet´s membrane, pointing to a possible iris injury. Conclusion Consequently, we highlighted that contact lenses can be useful, safe and inexpensive protective devices in upper eyelid procedures to protect the cornea against mechanical iatrogenic trauma.

Key points Reperfusion injury of the bowel occurred in 44% of patients with acute mesenteric ischemia treated by endovascular revascularization. A decreased bowel enhancement on initial CT (HR = 8.2), an occlusion of the superior mesenteric artery (HR = 7.0), an embolic cause (HR = 7.4), and higher initial serum lactate level (HR = 1.4) were identified as predictors of reperfusion injury. Bowel wall hypoattenuation, hyperenhancement of the mucosa, and increase in CRP levels after revascularization were key diagnostic features of reperfusion injury.

Abstract Aims Atrial fibrillation (AF)/atrial flutter is common during cardiac amyloidosis (CA). Electrical cardioversion (EC) is a strategy to restore sinus rhythm (SR). However, left atrial thrombus (LAT) represents a contraindication for EC. CA patients with AF/atrial flutter have a high prevalence of LAT. We aimed to evaluate EC characteristics, LAT prevalence and risk factors, and AF/atrial flutter outcome in CA patients undergoing EC, predominantly treated with direct oral anticoagulants (DOACs). Methods and results All patients with CA and AF/atrial flutter referred for the first time to our national referral centre of amyloidosis for EC from June 2017 to February 2021 were included in this study. In total, 66 patients (median age 74.5 [70;80.75] years, 67% male) were included with anticoagulation consisted of DOAC in 74% of cases. All patients underwent cardiac imaging before EC to rule out LAT. EC was cancelled due to LAT in 14% of cases. Complete thrombus resolution was observed in only 17% of cases. The two independent parameters associated with LAT were creatinine [hazard ratio (HR) = 1.01; confidence interval (CI) = 1.00–1.03, P = 0.036] and the use of antiplatelet agents (HR = 13.47; CI = 1.85–98.02). EC acute success rate was 88%, and we observed no complication after EC. With 64% of patients under amiodarone, AF/atrial flutter recurrence rate following EC was 51% after a mean follow‐up of 30 ± 27 months. Conclusions Left atrial thrombus was observed in 14% of CA patients listed for EC and mainly treated with DOAC. The acute EC success rate was high with no complication. The long‐term EC success rate was acceptable (49%).

Abstract Aims This study sought to describe and evaluate the impact of a routine in‐hospital cardiac resynchronization therapy (CRT) programme, including comprehensive heart failure (HF) evaluation and systematic echo‐guided CRT optimization. Methods and results CRT implanted patients were referred for optimization programme at 3 to 12 months from implantation. The program included clinical and biological status, standardized screening for potential cause of CRT non‐response and systematic echo‐guided atrioventricular and interventricular delays (AVd and VVd) optimization. Initial CRT‐response and improvement at 6 months post‐optimization were assessed with a clinical composite score (CCS). Major HF events were tracked during 1 year after optimization. A total of 227 patients were referred for CRT optimization and enrolled (71 ± 11 years old, 77% male, LVEF 30.6 ± 7.9%), of whom 111 (48.9%) were classified as initial non‐responders. Left ventricular lead dislodgement was noted in 4 patients (1.8%), and loss or ≤90% biventricular capture in 22 (9.7%), mostly due to arrhythmias. Of the 196 patients (86%) who could undergo echo‐guided CRT optimization, 71 (36.2%) required VVd modification and 50/144 (34.7%) AVd modification. At 6 months post‐optimization, 34.3% of the initial non‐responders were improved according to the CCS, but neither AVd nor VVd echo‐guided modification was significantly associated with CCS‐improvement. After one‐year follow‐up, initial non‐responders maintained a higher rate of major HF events than initial responders, with no significant difference between AVd/VVd modified or not. Conclusions Our study supports the necessity of a close, comprehensive and multidisciplinary follow‐up of CRT patients, without arguing for routine use of echo‐guided CRT optimization.

ABSTRACT Non-coding RNAs (sRNA) play a key role in controlling gene expression in bacteria, typically by base-pairing with ribosome binding sites to block translation. The modification of ribosome traffic along the mRNA generally affects its stability. However, a few cases have been described in bacteria where sRNAs can affect translation without a major impact on mRNA stability. To identify new sRNA targets in Bacillus subtilis potentially belonging to this class of mRNAs, we used pulsed-SILAC (stable isotope labeling by amino acids in cell culture) to label newly synthesized proteins after short expression of the RoxS sRNA, the best characterized sRNA in this bacterium. RoxS sRNA was previously shown to interfere with the expression of genes involved in central metabolism, permitting control of the NAD+/NADH ratio in B. subtilis. In this study, we confirmed most of the known targets of RoxS, showing the efficiency of the method. We further expanded the number of mRNA targets encoding enzymes of the TCA cycle and identified new targets. One of these is YcsA, a tartrate dehydrogenase that uses NAD+ as co-factor, in excellent agreement with the proposed role of RoxS in management of NAD+/NADH ratio in Firmicutes. IMPORTANCE Non-coding RNAs (sRNA) play an important role in bacterial adaptation and virulence. The identification of the most complete set of targets for these regulatory RNAs is key to fully identifying the perimeter of its function(s). Most sRNAs modify both the translation (directly) and mRNA stability (indirectly) of their targets. However, sRNAs can also influence the translation efficiency of the target primarily, with little or no impact on mRNA stability. The characterization of these targets is challenging. We describe here the application of the pulsed SILAC method to identify such targets and obtain the most complete list of targets for a defined sRNA.

Background Leaf symbiosis is a phenomenon in which host plants of Rubiaceae interact with bacterial endophytes within their leaves. To date, it has been found in around 650 species belonging to eight genera in four tribes; however, the true extent in Rubiaceae remains unknown. Our aim is to investigate the possible occurrence of leaf endophytes in the African plant genera Empogona and Tricalysia and, if present, to establish their identity. Methods Total DNA was extracted from the leaves of four species of the Coffeeae tribe (Empogona congesta, Tricalysia hensii, T. lasiodelphys, and T. semidecidua) and sequenced. Bacterial reads were filtered out and assembled. Phylogenetic analysis of the endophytes was used to reveal their identity and their relationship with known symbionts. Results All four species have non-nodulated leaf endophytes, which are identified as Caballeronia. The endophytes are distinct from each other but related to other nodulated and non-nodulated endophytes. An apparent phylogenetic or geographic pattern appears to be absent in endophytes or host plants. Caballeronia endophytes are present in the leaves of Empogona and Tricalysia, two genera not previously implicated in leaf symbiosis. This interaction is likely to be more widespread, and future discoveries are inevitable.

The formation of a stable and adherent oxide layer on the Ti-6Al-4V alloy can improve the mechanical and corrosion resistance of this material. This work studied the creep behavior of Ti-6Al-4V alloy after two different thermal oxidation conditions: at 650 °C for 12 h and at 800 °C for 2 h. In the XRD analysis of the oxidized samples, it was possible to observe the formation of rutile (TiO2) and a displacement of the peaks of α and β phases caused by the dissolution of oxygen. In the creep test at 550 °C, the material oxidized at 800 °C for 2 h showed a greater creep life at 125 MPa, the crack took longer to brake probably due to the greater thickness of the layer. At 550°C and 187.5 MPa the material oxidized at 650 °C for 12h has a better creep life, probably due to the layer more adhered.

Underground storage organs are poorly preserved in the archaeological record, and as a result their contribution to the diet of ancient societies is poorly understood. Starch grain analysis is a well-established methodology used in archaeology to reveal the use of various plants, including tubers, rhizomes, and roots. This paper presents the results of a study of starch grains recovered from millstones from various archaeological sites located in the Paris Basin. Our results highlight the use of tubers by these first agricultural populations at the beginning of the Neolithic (Linearbandkeramik and Blicquy-Villeneuve-Saint-Germain; 5200-4700 BC), providing new data on their contribution to the diet of agro-pastoral societies.

Introducción: el calcio es el electrolito más abundante del cuerpo humano y la hipercalcemia es el trastorno común causado normalmente por el hiperparatiroidismo primario o malignidad, su manejo depende de la presentación y causa subyacente. Además, una proporción de casos se presentan como una emergencia, lo que conlleva a una mortalidad significativa. Objetivo: mostrar un caso inusual de presentación clínica de hipercalcemia asociada a hiperparatiroidismo primario y, asimismo, dar una breve revisión acerca del enfoque y el manejo de esta patología. Presentación del caso: paciente femenina de 32 años, antecedente de adenoma paratiroideo no resecado y pancreatitis, asiste por tres días de dolor abdominal de tipo cólico y de moderada intensidad, acompañado de episodios eméticos de contenido alimentario, paraclínicos iniciales con hipercalcemia severa, electrocardiograma con bloqueo auriculoventricular grado I, gases arteriales con alcalosis respiratoria aguda e hiperlactatemia. También se le practicó un TAC de abdomen donde este apareció con tumores pardos. Se ingreso? a la UCI para la administración de líquidos endovenosos, diuréticos de asa y cinacalcet, pero no presentó mejoría, por lo que se indicó terapia de hemodiálisis. Discusión y conclusión: la hipercalcemia es un hallazgo frecuente. El hiperparatiroidismo primario y la neoplasia maligna son las dos causas más frecuentes de aumento de los niveles de calcio sérico y, en conjunto, representan alrededor del 90?% de todos los casos, donde los valores en suero varían entre el calcio total (8,5 y 10,5 mg/dl) y el iónico (1,16-1,31). La concentración sérica de Ca 2+ esta? estrechamente relacionada por las acciones de la hormona paratiroidea y el calcitriol, donde el hiperparatiroidismo primario ocurre como resultado de adenomas, hiperplasias y carcinoma. Las manifestaciones clínicas y la severidad van a estar correlacionadas con el tiempo de duración de la enfermedad, los niveles de calcio y de PTH. Dentro del tratamiento, este será guiado por su causa, sin embargo, es posible clasificarlo en tratamiento urgente y no urgente. Además, el enfoque de la hipercalcemia aguda severa es un reto diagnóstico dadas las múltiples causas que pueden llevar a este trastorno hidroelectrolítico y la rápida instauración de tratamiento que se requiere cuando es detectada.