Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study

: The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (p = 0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (p = 0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (p = 0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (p = 0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (p = 0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (p = 0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (p = 0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (p < 0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (p = 0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (p = 0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)

Modelisation et optimisation de la trempe de contour des pièces dentées

RÉSUMÉ:- En général, les mécaniciens mettent en œuvre, pour assurer la fiabilité et la pérennité, des machines qu'ils conçoivent. Et pourtant, des défauts (déformation, fissures et irrégularité des profondeurs trempées) surviennent, tantôt de façon aléatoire, tantôt de façon répétée. Après avoir traité la trempe superficielle par induction des pièces de géométries simples (cylindriques) [1], nous proposons donc de traiter la trempe de contour des pièces dentées de type engrenages, roues dentées, …, et plus précisément le profil des dents d'une roue dentées. Dans cet article nous présenterons une approche intéressante basée sur la recherche d'une fréquence optimale du générateur. Nous faisons appel à trois techniques variées : Trempe de contour mono fréquence, Trempe bi-fréquences et Trempe bi-fréquences bi-couches pour en choisir la meilleure description du contour trempé. le choix définitif de la technique sera confirmé, à la fin de ce travail, par une simulation et traitement d'un pignon. Mots clés : Chauffage inductif, Trempe de contour, fréquence optimale, engrenage. ABSTRACT:- In general, mechanics put in work to assure reliability and the everlastingness of machines that they conceive. And yet, of defaults (distortion, cracks and irregularity of quenched depths) occur, soon of uncertain way, soon of repeated way. After have treated the superficial quench by induction of the simple geometry pieces (cylindrical) [1], we propose to treat the quenching contour of toothed pieces type gearings, toothed wheels, therefore…, more precisely the profile of teeth of a wheel. In this paper we will present an approach interesting based on the research of an optimal frequency of the generator. We make call to three varied techniques: Quenching of contour mono frequency, Quenching bi-frequency and Quenching bi-frequency bilies to choose the best description of the contour quenched. Key Words: Inductive heating, Quenching of contour, optimal frequency, gearing African Journal of Science and Technology Vol.4(2) 2003:95-10

Évolution des caractéristiques de l’interface d’une structure traitée superficiellement par induction

La trempe par induction reste actuellement l’opération de durcissement superficiel la plus intéressante par sa simplicité d’emploi et sa productivité élevée. En pratique, la profondeur de trempe est considérée comme paramètre principal pour tester l’efficacité d’un tel durcissement. Dans cet article, nous proposons d’étudier l’effet des paramètres d’induction sur la profondeur de trempe et de comprendre l’évolution de la structure dans l’interface (zone comprise entre la couche trempée et la structure initiale). Dans cette voie, il a pu être montré qu’il était possible de contrôler la microstructure de la couche superficielle en passant par l’interface et même jusqu’au cœur d’une éprouvette cylindrique. Une relation entre la dureté et la profondeur de trempe a été proposée pour décrire l’évolution de l’interface en fonction des paramètres du procédé. Cette relation a été validée expérimentalement en montrant une concordance intéressante avec les résultats numériques

Empirical models for estimating the mechanical and morphological properties of recycled low density polyethylene/snail shell bio-composites

The empirical models for estimating the mechanical properties and morphological of recycled low density polyethylene/snail shell bio-composites was investigated. The snail shell of particle sizes 75, 125, 250 and 500 μm with a weight percentage of 0, 5, 10 and 15 (wt%) with recycled polyethylene (RLDPE) were prepared by compounding and compressive moulding technique. Samples were cut from the panel and subjected to mechanical testing such as tensile, flexural and impact energy. Scanning electron microscope was used to analyse the fracture surface of the samples. Linear regression equation and analysis of variance (ANOVA) were employed to investigate the influence of process parameters on the mechanical properties of the samples. Results obtained showed that: as the wt% snail shell particles increased from 5 to 15, there was a raise in the tensile strength by (2.69) and the flexural strength (1.53). Also the increase in the snail shell particle size from 75 to 500 μm decreased the tensile strength by −5.46, flexural strength −3.97 and impact energy by −1.97. The predicted results obtained were in good agreement with the experimental results. Hence, the work can be used for indoor and outdoor structural applications

Runge-Kutta-Nyström Pairs of Orders 8(6) with Coefficients Trained to Perform Best on Classical Orbits

In this study, we consider eight stages per step family of explicit Runge-Kutta-Nyström pairs of orders eight and six. The pairs from this family effectively use eight stages for each step. The coefficients provided by such a method are much less than the number of non linear order conditions required to be solved. Thus, we traditionally apply various simplified assumptions in order to address this drawback. The assumptions taken in the family we consider here deliver a subsystem where all the coefficients are evaluated successively and explicitly with respect to five free parameters. We train (adjust) these free parameters in order to derive a certain pair that outperforms other similar pairs of orders 8(6) in Keplerian type orbits, e.g., Kepler, perturbed Kepler, Arenstorf orbit, or Pleiades. Differential evolution technique is used for the training. The pair that we finally present offers about an additional digit of accuracy in a variety of orbits. © 2022 by the authors. Licensee MDPI, Basel, Switzerland