Solvent effect modelling of isocyanuric products synthesis by chemometric methods

Chemometric tools were used to generate the modelling of solvent e¡ects on the N-alkylation of an isocyanuric acid salt. The method proceeded from a central composite design applied on the Carlson solvent classification using principal components analysis. The selectivity of the reaction was studied from the production of different substituted isocyanuric derivatives. Response graphs were obtained for each compound and used to devise a strategy for solvent selection. The prediction models were validated and used to search for the best selectivity for the reaction system. The solvent most often selected as the best for the reaction is the N,N-dimethylformamide

Liver transplantation as a new standard of care in patients with perihilar cholangiocarcinoma?:Results from an international benchmark study

Objective: To define benchmark values for liver transplantation (LT) in patients with perihilar cholangiocarcinoma (PHC) enabling unbiased comparisons.Background: Transplantation for PHC is used with reluctance in many centers and even contraindicated in several countries. Although benchmark values for LT are available, there is a lack of specific data on LT performed for PHC.Methods: PHC patients considered for LT after Mayo-like protocol were analyzed in 17 reference centers in 2 continents over the recent 5-year period (2014–2018). The minimum follow-up was 1 year. Benchmark patients were defined as operated at high-volume centers (≥ 50 overall LT/year) after neoadjuvant chemoradiotherapy, with a tumor diameter &lt;3 cm, negative lymph nodes, and with the absence of relevant comorbidities. Benchmark cutoff values were derived from the 75th to 25th percentiles of the median values of all benchmark centers.Results: One hundred thirty-four consecutive patients underwent LT after completion of the neoadjuvant treatment. Of those, 89.6% qualified as benchmark cases. Benchmark cutoffs were 90-day mortality ≤ 5.2%; comprehensive complication index at 1 year of ≤ 33.7; grade ≥ 3 complication rates ≤ 66.7%. These values were better than benchmark values for other indications of LT. Five-year disease-free survival was largely superior compared with a matched group of nodal negative patients undergoing curative liver resection (n = 106) (62% vs 32%, P &lt; 0.001).Conclusion: This multicenter benchmark study demonstrates that LT offers excellent outcomes with superior oncological results in early stage PHC patients, even in candidates for surgery. This provocative observation should lead to a change in available therapeutic algorithms for PHC.</p

A multicentre outcome analysis to define global benchmarks for donation after circulatory death liver transplantation

BACKGROUND: To identify the best possible outcomes in liver transplantation from donation after circulatory death donors (DCD) and to propose outcome values, which serve as reference for individual liver recipients or patient groups. METHODS: Based on 2219 controlled DCD liver transplantations, collected from 17 centres in North America and Europe, we identified 1012 low-risk, primary, adult liver transplantations with a laboratory MELD of ≤20points, receiving a DCD liver with a total donor warm ischemia time of ≤30minutes and asystolic donor warm ischemia time of ≤15minutes. Clinically relevant outcomes were selected and complications were reported according to the Clavien-Dindo-Grading and the Comprehensive Complication Index (CCI). Corresponding benchmark cut-offs were based on median values of each centre, where the 75(th)-percentile was considered. RESULTS: Benchmark cases represented between 19.7% and 75% of DCD transplantations in participating centers. The one-year retransplant and mortality rate was 5.23% and 9.01%, respectively. Within the first year of follow-up, 51.1% of recipients developed at least one major complication (≥Clavien-Dindo-Grade-III). Benchmark cut-offs were ≤3days and ≤16days for ICU and hospital stay, ≤66% for severe recipient complications (≥Grade-III), ≤16.8% for ischemic cholangiopathy, and ≤38.9CCI points at one-year posttransplant. Comparisons with higher risk groups showed more complications and impaired graft survival, outside the benchmark cut-offs. Organ perfusion techniques reduced the complications to values below benchmark cut-offs, despite higher graft risk. CONCLUSIONS: Despite excellent 1-year survival, morbidity in benchmark cases remains high with more than half of recipients developing severe complications during 1-year follow-up. Benchmark cut-offs targeting morbidity parameters offer a valid tool to assess the protective value of new preservation technologies in higher risk groups, and provide a valid comparator cohort for future clinical trials. LAY SUMMARY: The best possible outcomes after liver transplantation of grafts donated after circulatory death (DCD) were defined using the concept of benchmarking. These were based on 2219 liver transplantations following controlled DCD donation in 17 centres worldwide. The following benchmark cut-offs for the most relevant outcome parameters were developed: ICU and hospital stay: ≤3 and ≤16 days; primary non function: ≤2.5%; renal replacement therapy: ≤9.6%; ischemic cholangiopathy: ≤16.8% and anastomotic strictures ≤28.4%. One-year graft loss and mortality were defined as ≤14.4% and 9.6%, respectively. Donor and recipient combinations with higher risk had significantly worse outcomes. The use of novel organ perfusion technology achieved similar, good results in this high-risk group with prolonged donor warm ischemia time, when compared to the benchmark cohort

Le Désir, « un feu à jamais insatiable » – variation autour d’un quatrain sanskrit (shloka) qui évoque la soif inextinguible des sens

Poème en sanskrit : in Abel Bergaigne, Manuel pour étudier la langue sanskrite, éd. Honoré Champion (1re édition 1884), 1971, p. 36, strophe 220. Transcription nāstyanyā tr̥ṣṇayā tulyākā citstrī subhagā kva cityā prāṇānapi muñcantībhavatyevādhikapriyā Traduction Nulle part n’existe une femmeAussi aimée que la luxure :Même en nous vidant de nos forcesElle reste la bien-aimée. Quand on lit un texte sanskrit (poésie, épopée, contes, métaphysique…), et que l’on choisit comme dictionnaire le conte..

Traduire Manas & Kâma : L’histoire de la reine Ahalyâ et du jeune Indra, fils de brahmane ou « La Dame de mes pensées »

Transcription Poème en sanskrit : Bhagavad Gîtâ, ii, 70 āpūryamāṇamacalapratiṣṭaṃsamudramāpaḥ praviśanti yadvat /tadvatkāmā yaṃ praviśyanti sarvesa śāntimāpnoti na kāmakāmi Traduction Celui en qui les désirs se perdentcomme les eaux se perdentdans l’océan,lequel s’emplit sans cesseet pourtant demeure immuable,cet homme atteint à la sérénité,il ne poursuit plus de désirs. L’union du mot et de la chose est-il un mariage de raison ou un mariage d’amour ? On observe l’apparition d’une bien jolie ..

L’évolution de la chaire de chimie industrielle de 1935 à 2012

International audienc

Soft oxidation of graphite studied by XPS and STM

The modification of the graphite surface after weak oxidation using a nitric acid solution has been studied by X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM). A new corrugation at the atomic scale has been revealed by STM on the basal planes. It is attributed to the presence, in other respects demonstrated by XPS, of some oxygenated groups created by oxidation and regularly distributed on the surface. This soft oxidation conserves the graphite basal planes and is interpreted by an oxygen chemisorption on graphite through a bond involving π electrons of the aromatic cell. Organic groups which need dangling σ bonds to fix on the surface should preferencially attach on ridges of large defects.La modification de la surface de graphite après une faible oxydation dans une solution d'acide nitrique a été étudiée par spectroscopie de photoélectrons (XPS) et par microscopie tunnel (STM). Une nouvelle corrugation a été mise en évidence à l'échelle atomique par STM sur les plans de base du graphite. Elle est attribuée à la présence d'autre part démontrée par XPS, de groupements organiques créés par l'oxydation et distribués de façon régulière sur la surface. Cette oxydation douce n'altère pas les plans de base du graphite et est interprétée par la chimisorption d'atomes d'oxygène sur le graphite, les liaisons s'effectuant à partir d'électrons π de la cellule aromatique. Les groupements organiques nécessitant des liaisons pendantes σ pour se fixer sur la surface semblent se positionner préférentiellement sur les arètes de gros défauts physiques