21 research outputs found
The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy
Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations.
Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (>â90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves.
Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45â85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations >â90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SEâ=â0.013, pââ90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score.
Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care
Surface Organometallic Chemistry on Zeolites: Synthesis of Group IV Metal Alkyls and Metal Hydrides on Hierarchical Mesoporous HâZSMâ5
Surface organometallic chemistry (SOMC) has mainly been
devoted
to the reaction of organometallics with surfaces comprising highly
divided and dehydroxylated oxides. The field has been extended to
SOMC on metal nanoparticles. However, to the best of our knowledge,
SOMC has not been extended to hierarchical fibrous zeolites, although
zeolitic materials are a particular class of oxides. Zeolite catalysis
is important in hydrocarbon industrial chemistry. However, having
an optimum balance between the activity and selectivity of the zeolitic
catalysts remains a major challenge in the field. The main difficultly
is the plethora of surface sites, only some of which are catalytically
active. Given that the acidoâbasic properties and porosity
of zeolites are especially important to the refining and petrochemical
industries, we decided to explore this rather unexplored area. Here,
three novel well-defined single-site materials [(Np)3M@ZSM-5,
M = Ti, Zr, and Hf] supported on a hierarchical mesoporous H-ZSM-5
material (1) are reported. They are prepared using the
concepts and tools of SOMC. They are further converted to their corresponding
metal hydride [(H)nM@ZSM-5, M = Ti, Zr,
and Hf, (n = 1â2)] materials (5â7) through controlled hydrogenolysis of [(SiâOâ)M(Np)3, M = Ti, Zr, and Hf] materials (2â4)
under H2 (1 atm) at 150 °C for 16 h. All these surface
catalysts are characterized by various spectroscopic techniques including
Fourier transform infrared spectroscopy, elemental analysis, solid-state
NMR spectroscopy, powder X-ray diffraction, BrunauerâEmmettâTeller
surface area measurements, and scanning electron microscopy and high-resolution
transmission electron microscopy analyses and are supported by density
functional theory calculations. The catalytic activity of these well-defined
single-site novel materials will be tested for the catalytic applications
in petrochemistry for refinery processes such as hydrocracking of
distillates from crude oil or intermediate refinery process streams
to useful petroleum value-added products for the society
Enseigner et apprendre Ă l'Ăšre de l'intelligence artificielle
International audienceAs part of the Digital Working Group (GTnum) #Scol_IA âRenewal of digital practices and creative uses of digital and AIâ we are pleased to present the white paper âTeaching and learning in the era of Artificial Intelligence, Acculturation , integration and creative uses of AI in educationâ. The white paper edited by Margarida Romero, Laurent Heiser and Alexandre Lepage aims to provide the various educational actors with a diversified perspective both on the issues of acculturation and training in AI and on the resources and feedback from the various research teams and organisations. of scientific culture in the French-speaking countries. A multidisciplinary approach makes it possible to consider the perspectives of researchers in computer science as well as those of education and training sciences, information and communication sciences and the expertise of teaching professionals. and scientific mediation.Dans le cadre du Groupe de Travail numĂ©rique (GTnum) #Scol_IA âRenouvellement des pratiques numĂ©riques et usages crĂ©atifs du numĂ©rique et IAâ nous sommes heureux de vous prĂ©senter le livre blanc âEnseigner et apprendre Ă lâĂšre de lâIntelligence Artificielle, Acculturation, intĂ©gration et usages crĂ©atifs de lâIA en Ă©ducationâ. Le livre blanc Ă©ditĂ© par Margarida Romero, Laurent Heiser et Alexandre Lepage vise apporter aux diffĂ©rents acteurs Ă©ducatifs un Ă©clairage diversifiĂ© tant des enjeux de lâacculturation et formation Ă lâIA que des ressources et retours dâexpĂ©rience des diffĂ©rentes Ă©quipes de recherche et organismes de culture scientifique de la francophonie. Une approche pluridisciplinaire permet de considĂ©rer tant les perspectives des chercheurs en sciences de lâinformatique, que celles des sciences de lâĂ©ducation et de la formation, les sciences de lâinformation et la communication et lâexpertise des professionnels de lâenseignement et de la mĂ©diation scientifique