Machine Learning-Based Analysis in the Management of Iatrogenic Bile Duct Injury During Cholecystectomy: a Nationwide Multicenter Study

Background Iatrogenic bile duct injury (IBDI) is a challenging surgical complication. IBDI management can be guided by artificial intelligence models. Our study identified the factors associated with successful initial repair of IBDI and predicted the success of definitive repair based on patient risk levels. Methods This is a retrospective multi-institution cohort of patients with IBDI after cholecystectomy conducted between 1990 and 2020. We implemented a decision tree analysis to determine the factors that contribute to successful initial repair and developed a risk-scoring model based on the Comprehensive Complication Index. Results We analyzed 748 patients across 22 hospitals. Our decision tree model was 82.8% accurate in predicting the success of the initial repair. Non-type E (p < 0.01), treatment in specialized centers (p < 0.01), and surgical repair (p < 0.001) were associated with better prognosis. The risk-scoring model was 82.3% (79.0-85.3%, 95% confidence interval [CI]) and 71.7% (63.8-78.7%, 95% CI) accurate in predicting success in the development and validation cohorts, respectively. Surgical repair, successful initial repair, and repair between 2 and 6 weeks were associated with better outcomes. Discussion Machine learning algorithms for IBDI are a novel tool may help to improve the decision-making process and guide management of these patients

Érosion du sol et sédimentation fluviale dans les «ramblas» du sud-est espagnol

The importance of erosion by water in the semi-arid regions of South East Spain is well known. Quantifying the amount of erosion is complicated involving serious problems of instrumentation and estimation. This preoccupation for evaluating the magnitude of erosion is shown in this paper, in which the quantity of potential soil erosion, sediment delivery ratios and sediment yields are calculated for various hydrological units. The GAMES model (Guelph Model for evaluating the effects of Agricultural Management Systems on Erosion and Sedimentation) was used to calculate the necesary parameters and applied to five drainage basins with different physical characteristics and land uses for the autumn period (the season in which the greatest amount of annual erosion occurs in this mediterranean region).L'importance de l'érosion hydrique dans les terres semi-arides du Sud-Est espagnol est très connue. L'évaluation quantitative de cette érosion est complexe parce qu'elle pose de graves problèmes d'ajustement empirique et d outils pratiques abordés dans cet article. L' évaluation de l'érosion potentielle, les indices de libération d'apports fluviaux et de production de sédiments sont calculés pour différentes unités hydrologiques. Le modèle GAMES a été utilisé pour calculer les paramètres d'érosion et appliqué à cinq bassins dont les caractéristiques physiques et l'utilisation du sol sont différents, pendant l'automne (saison qui montre la plus grande quantité d'érosion hydrique annuelle dans cette région méditerranéenne).Conesa Garcia Carmelo. Érosion du sol et sédimentation fluviale dans les «ramblas» du sud-est espagnol. In: Méditerranée, tome 71, 3-4-1990. L'agriculture en terrasses sur les versants méditerranéens; histoire, conséquences sur l'évolution du milieu. Séminaire - Aix-en-Provence - 3 février 1990, sous la direction de Mireille Provansal . pp. 63-74

Hydraulic Geometry, GIS and Remote Sensing, Techniques against Rainfall-Runoff Models for Estimating Flood Magnitude in Ephemeral Fluvial Systems

This paper shows the combined use of remotely sensed data and hydraulic geometry methods as an alternative to rainfall-runoff models. Hydraulic geometric data and boolean images of water sheets obtained from satellite images after storm events were integrated in a Geographical Information System. Channel cross-sections were extracted from a high resolution Digital Terrain Model (DTM) and superimposed on the image cover to estimate the peak flow using HEC-RAS. The proposed methodology has been tested in ephemeral channels (ramblas) on the coastal zone in south-eastern Spain. These fluvial systems constitute an important natural hazard due to their high discharges and sediment loads. In particular, different areas affected by floods during the period 1997 to 2009 were delimited through HEC-GeoRAs from hydraulic geometry data and Landsat images of these floods (Landsat‑TM5 and Landsat-ETM+7). Such an approach has been validated against rainfall-surface runoff models (SCS Dimensionless Unit Hydrograph, SCSD, Témez gamma HU Tγ and the Modified Rational method, MRM) comparing their results with flood hydrographs of the Automatic Hydrologic Information System (AHIS) in several ephemeral channels in the Murcia Region. The results obtained from the method providing a better fit were used to calculate different hydraulic geometry parameters, especially in residual flood areas

Hydraulic Geometry, GIS and Remote Sensing, Techniques against Rainfall-Runoff Models for Estimating Flood Magnitude in Ephemeral Fluvial Systems

This paper shows the combined use of remotely sensed data and hydraulic geometry methods as an alternative to rainfall-runoff models. Hydraulic geometric data and boolean images of water sheets obtained from satellite images after storm events were integrated in a Geographical Information System. Channel cross-sections were extracted from a high resolution Digital Terrain Model (DTM) and superimposed on the image cover to estimate the peak flow using HEC-RAS. The proposed methodology has been tested in ephemeral channels (ramblas) on the coastal zone in south-eastern Spain. These fluvial systems constitute an important natural hazard due to their high discharges and sediment loads. In particular, different areas affected by floods during the period 1997 to 2009 were delimited through HEC-GeoRAs from hydraulic geometry data and Landsat images of these floods (Landsat‑TM5 and Landsat-ETM+7). Such an approach has been validated against rainfall-surface runoff models (SCS Dimensionless Unit Hydrograph, SCSD, Témez gamma HU Tγ and the Modified Rational method, MRM) comparing their results with flood hydrographs of the Automatic Hydrologic Information System (AHIS) in several ephemeral channels in the Murcia Region. The results obtained from the method providing a better fit were used to calculate different hydraulic geometry parameters, especially in residual flood areas

Changes in stream power and morphological adjustments at the event-scale and high spatial resolution along an ephemeral gravel-bed channel

[EN] Sediment budgets and morphological channel adjustments are closely related to changes in stream power. In ephemeral channels, whose geomorphic response depends on the magnitude and frequency of hydrological events isolated in time, such relationships are often difficult to establish. This study sought to quantitatively relate morphological adjustments to stream power along different reference channel reaches for the period 2018¿2020 in the Azohía Rambla, a Mediterranean gravel-bed ephemeral stream in southeastern Spain. Very high resolution digital terrain models (VHR DTM) (at 1 to 2.5 cm pixel size), combined with ortophotographs and 3D point clouds, generated via SfM photogrammetry and terrestrial laser scanning (TLS) for pre- and post-event stages, together with ground-based surveys were used to estimate the spatial variability of morphological sediment budgets and to assess channel bed mobility and changes in net sediment flux during the study period in two spatial scenarios: reference channel reaches (RCRs) and pilot bed survey areas (PBSAs). The hydraulic variables (flow velocity, Froude number, shear stress, mean stream power and energy gradient, among other) were estimated using a 1D hydrodynamic model calibrated with field information. The high resolution maps allowed a spatially-explicit analysis of stream power and transport efficiency in accordance with the areas of erosion and deposition in each RCR. The incision and bed armoring processes showed different trends according to the stream power (¿), cumulative excess energy (¿c), and relative bed stability (RBS). The greatest morphological adjustments at the event scale coincided with ¿ values above 300W m¿2, ¿c higher than 3 MJ, and RBS below 0.5. The relationships between the mean stream power gradient at peak flood discharges and the changes in bed elevation verified the bed aggradation (an average surface raising of 0.17 to 0.22 m for ¿¿/¿s of ¿6.2 to ¿14.5Wm¿2 m¿1) during the major flood and bed scour (average surface lowering of 0.16 to 0.19 m for ¿¿/¿s of 5.8 to 10.6 W m¿2 m¿1) in the moderated events at the bankfull and sub-bankfull stages. Furthermore, this study contributes new relevant data to the scarce existing literature on the relationships between stream power and morphosedimentary adjustments in a fluvial system highly sensitive and resilient to climate change, as is the case of ephemeral gravel-bed channels.This work has been financed by ERDF/Spanish Ministry of Science, Innovation and Universities-State Research Agency (AEI) /Project CGL2017-84625-C2-1-R (CCAMICEM) ; State Program for Research, Development and Innovation oriented to the Challenges of Society, and by the University of Alicante (Project GRE18-15) . We also would like to extend our thanks to AEMET and the Segura River Hydrographic Confederation Center (SHC) , Government of Spain, for their collaboration.Conesa-Garcia, C.; Puig-Mengual, C.; Riquelme, A.; Tomás, R.; Martinez-Capel, F.; Garcia-Lorenzo, R.; Pastor, JL.... (2022). Changes in stream power and morphological adjustments at the event-scale and high spatial resolution along an ephemeral gravel-bed channel. Geomorphology. 398:1-25. https://doi.org/10.1016/j.geomorph.2021.10805312539

Where Brain, Body and World Collide

The production cross section of electrons from semileptonic decays of beauty hadrons was measured at mid-rapidity (|y| &lt; 0.8) in the transverse momentum range 1 &lt; pt &lt; 8 Gev/c with the ALICE experiment at the CERN LHC in pp collisions at a center of mass energy sqrt{s} = 7 TeV using an integrated luminosity of 2.2 nb^{-1}. Electrons from beauty hadron decays were selected based on the displacement of the decay vertex from the collision vertex. A perturbative QCD calculation agrees with the measurement within uncertainties. The data were extrapolated to the full phase space to determine the total cross section for the production of beauty quark-antiquark pairs