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Le raffineur achète des pétroles bruts, de différentes qualités et d'origines variées, et il fabrique un certain nombre de produits répondant à des spécifications de qualité pour les vendre dans des proportions correspondant aux besoins du marché. Il est nécessaire pour cela d'assurer l'équilibre général entre l'approvisionnement en brut et la demande du marché en produits finis. Les facteurs traduisant l'évolution des pétroles bruts (souci de diversification géographique et politique, désir des producteurs de traiter les bruts faciles et d'exporter les lourds, compétitivité de plus en plus grande des bruts non-conventionnels, grande disponibilité d'huiles lourdes) montrent l'alourdissement progressif des approvisionnements. L'enchérissement des produits pétroliers provoque de plus en plus un allègement des besoins du marché (légère augmentation des carburants, baisse des distillats moyens, chute importante des fuels lourds). Du fait de l'alourdissement des bruts conventionnels, de la grande disponibilité des huiles lourdes et de l'allègement considérable du marché des produits finis, il devient nécessaire d'utiliser des charges de plus en plus lourdes dans les procédés de conversion. La production d'oléfines peut s'effectuer à partir d'une gamme très large de coupes pétrolières, mais lorsqu'on cherche à alourdir la charge des unités de pyrolyse, il faut se poser les questions suivantes : - quelle est la souplesse des unités existantes et à venir par rapport à la charge ? - quelle est la limite industrielle et l'alourdissement de la charge ? - quel est le rôle des impuretés sur le fonctionnement des unités ? - quels sont les problèmes technologiques posés par le traitement de ces charges ? - qu'en est-il de l'amélioration des bilans énergétiques et économiques lorsque la charge s'alourdit ? A refiner buys crude oils of different qualities and varying origins and he manufactures a certain number of products meeting quality specifications for sale in proportions corresponding to the needs of the market. For this, a general balance must be attained between the supply of crude oil and the demand for finished products by the market. The factors that show crude oils are evolving (preoccupation with geographic and political diversification, desire by producers to process easy crudes and to export heavy crudes, more or less extensive competitivity of unconventional crudes, great availability of heavy oils) indicate that supplies are gradually becoming heavier. The increasing cost of petroleum products is causing a greater and greater lightening of market requirements (slight increase in fuels, decrease in middle distillates, sharp drop in heavy fuel oils). Because conventional oils are becoming heavier, the great availability of heavy oils and the considerable lightening of the market for finished products, it is becoming necessary to use heavier and heavier feedstocks in conversion processes. Olefins can be produced from a very wide range of oil cuts, but when an attempt is made to use heavier feeds in pyrolysis units, then the following questions must be asked: (a) what is the flexibility of existing and future plants with respect to the feedstock? (b) what is the industrial limit to using heavier feedstocks? (c) what is the role of impurities on the operating of plants? (d) what technological problems are raised by processing such feedstocks? (e) what happens to the improvement of energy and economic balances when the feedstock gets heavier?

Abstract Background and aims Treatment with tumor necrosis factor α (TNFα) antagonists in IBD patients suffers from primary non-response rates of up to 40%. Biomarkers for early prediction of therapy success are missing. We investigated the dynamics of gene expression and DNA methylation in blood samples of IBD patients treated with the TNF antagonist infliximab and analyzed the predictive potential regarding therapy outcome. Methods We performed a longitudinal, blood-based multi-omics study in two prospective IBD patient cohorts receiving first-time infliximab therapy (discovery: 14 patients, replication: 23 patients). Samples were collected at up to 7 time points (from baseline to 14 weeks after therapy induction). RNA-sequencing and genome-wide DNA methylation data were analyzed and correlated with clinical remission at week 14 as a primary endpoint. Results We found no consistent ex ante predictive signature across the two cohorts. Longitudinally upregulated transcripts in the non-remitter group comprised TH2- and eosinophil-related genes including ALOX15, FCER1A, and OLIG2. Network construction identified transcript modules that were coherently expressed at baseline and in non-remitting patients but were disrupted at early time points in remitting patients. These modules reflected processes such as interferon signaling, erythropoiesis, and platelet aggregation. DNA methylation analysis identified remission-specific temporal changes, which partially overlapped with transcriptomic signals. Machine learning approaches identified features from differentially expressed genes cis-linked to DNA methylation changes at week 2 as a robust predictor of therapy outcome at week 14, which was validated in a publicly available dataset of 20 infliximab-treated CD patients. Conclusions Integrative multi-omics analysis reveals early shifts of gene expression and DNA methylation as predictors for efficient response to anti-TNF treatment. Lack of such signatures might be used to identify patients with IBD unlikely to benefit from TNF antagonists at an early time point.

Chronic inflammatory diseases (CID) are emerging disorders which do not only affect specific organs with respective clinical symptoms but can also affect various aspects of life, such as emotional distress, anxiety, fatigue and quality of life. These facets of chronic disease are often not recognized in the therapy of CID patients. Furthermore, the symptoms and patient-reported outcomes often do not correlate well with the actual inflammatory burden. The discrepancy between patient-reported symptoms and objectively assessed disease activity can indeed be instructive for the treating physician to draw an integrative picture of an individual’s disease course. This poses a challenge for the design of novel, more comprehensive disease assessments. In this mini-review, we report on the currently available patient-reported outcomes, the unmet needs in the field of chronic inflammatory diseases and the challenges of addressing these.

Discusses how Vietnamese cinema is beginning to be appreciated for its aesthetic qualities and for the picture it provides of Vietnam and its history. Why the late 1980s were a crucial period for the art form and for the nation as a whole; The content and form of Vietnamese films; Government and film makers; Education and influences; Documentary and scientific films; Characteristics of Vietnamese cinema; Themes of Vietnamese cinema.