1,348 research outputs found
Towards A System-Based Model For Overall Performance Evaluation In A Supply Chain Context
International audienceThe paper deals with the wide issue of overall performance expression of a system made of interacting entities. Formal aspects of overall performance expression are considered as a first step of this reflection in the context of supply chains (SC's). Indeed, a SC being a network of interconnected business entities, it is proposed to consider it as a system of systems. Because system behavior depends on process dynamics, the performance of any company of the SC highly depends on the performance of its processes. However, while process performance is clearly defined in the literature, performance of complex systems or systems of systems is more difficult to assess due to process interactions. The overall performance concept is usually unsatisfactory either for each company or for the whole SC. To express such performance in SC's, recent proposals have focused on the performance of the prime manufacturer. This performance being linked to the ones of the suppliers, the impact of supplier performances on the prime manufacturer performance has to be integrated. It is therefore proposed to respectively use the SCOR model for describing the involved sub-system processes and, from a computational point of view, to use the MAUT (Multi Attribute Utility Theory) MACBETH methodology to consistently compute the expected performances. More specifically, the Choquet integral is used as the aggregation operator to handle interactions between systems and processes. The case of a bearings manufacturer is used to illustrate the proposal for a supplier selection problem
Indirect techniques in nuclear astrophysics. Asymptotic Normalization Coefficient and Trojan Horse
Owing to the presence of the Coulomb barrier at astrophysically relevant
kinetic energies it is very difficult, or sometimes impossible, to measure
astrophysical reaction rates in the laboratory. That is why different indirect
techniques are being used along with direct measurements. Here we address two
important indirect techniques, the asymptotic normalization coefficient (ANC)
and the Trojan Horse (TH) methods. We discuss the application of the ANC
technique for calculation of the astrophysical processes in the presence of
subthreshold bound states, in particular, two different mechanisms are
discussed: direct capture to the subthreshold state and capture to the
low-lying bound states through the subthreshold state, which plays the role of
the subthreshold resonance. The ANC technique can also be used to determine the
interference sign of the resonant and nonresonant (direct) terms of the
reaction amplitude. The TH method is unique indirect technique allowing one to
measure astrophysical rearrangement reactions down to astrophysically relevant
energies. We explain why there is no Coulomb barrier in the sub-process
amplitudes extracted from the TH reaction. The expressions for the TH amplitude
for direct and resonant cases are presented.Comment: Invited talk on the Conference "Nuclear Physics in Astrophysics II",
Debrecen, Hungary, 16-20 May, 200
Measurement of the 20 and 90 keV resonances in the N reaction via THM
The reaction is of primary importance in
several astrophysical scenarios, including fluorine nucleosynthesis inside AGB
stars as well as oxygen and nitrogen isotopic ratios in meteorite grains. Thus
the indirect measurement of the low energy region of the reaction has been performed to reduce the nuclear
uncertainty on theoretical predictions. In particular the strength of the 20
and 90 keV resonances have been deduced and the change in the reaction rate
evaluated.Comment: 4 pages, 4 figures, submitted to PR
Social competence in pediatric brain tumor survivors: application of a model from social neuroscience and developmental psychology.
Pediatric brain tumor (BT) survivors are at risk for psychosocial late effects across many domains of functioning, including neurocognitive and social. The literature on the social competence of pediatric BT survivors is still developing and future research is needed that integrates developmental and cognitive neuroscience research methodologies to identify predictors of survivor social adjustment and interventions to ameliorate problems. This review discusses the current literature on survivor social functioning through a model of social competence in childhood brain disorder and suggests future directions based on this model. Interventions pursuing change in survivor social adjustment should consider targeting social ecological factors
Low oxygen tension primes aortic endothelial cells to the reparative effect of tissue-protective cytokines
Erythropoietin (EPO) has both erythropoietic and tissue-protective properties. The EPO analogues carbamylated EPO (CEPO) and pyroglutamate helix B surface peptide (pHBSP) lack the erythropoietic activity of EPO but retain the tissue-protective properties that are mediated by a heterocomplex of EPO receptor (EPOR) and the β common receptor (βCR). We studied the action of EPO and its analogues in a model of wound healing where a bovine aortic endothelial cells (BAECs) monolayer was scratched and the scratch closure was assessed over 24 h under different oxygen concentrations. We related the effects of EPO and its analogues on repair to their effect on BAECs proliferation and migration (evaluated using a micro-Boyden chamber). EPO, CEPO and pHBSP enhanced scratch closure only at lower oxygen (5%), while their effect at atmospheric oxygen (21%) was not significant. The mRNA expression of EPOR was doubled in 5% compared to 21% oxygen, and this was associated with increased EPOR assessed by immunofluorescence and Western blot. By contrast βCR mRNA levels were similar in 5% and 21% oxygen. EPO and its analogues increased both BAECs proliferation and migration, suggesting that both may be involved in the reparative process. The priming effect of low oxygen tension on the action of tissue-protective cytokines may be of relevance to vascular disease, including atherogenesis and restenosis
Consensus on circulatory shock and hemodynamic monitoring. Task force of the European Society of Intensive Care Medicine.
OBJECTIVE: Circulatory shock is a life-threatening syndrome resulting in multiorgan failure and a high mortality rate. The aim of this consensus is to provide support to the bedside clinician regarding the diagnosis, management and monitoring of shock.
METHODS: The European Society of Intensive Care Medicine invited 12 experts to form a Task Force to update a previous consensus (Antonelli et al.: Intensive Care Med 33:575-590, 2007). The same five questions addressed in the earlier consensus were used as the outline for the literature search and review, with the aim of the Task Force to produce statements based on the available literature and evidence. These questions were: (1) What are the epidemiologic and pathophysiologic features of shock in the intensive care unit ? (2) Should we monitor preload and fluid responsiveness in shock ? (3) How and when should we monitor stroke volume or cardiac output in shock ? (4) What markers of the regional and microcirculation can be monitored, and how can cellular function be assessed in shock ? (5) What is the evidence for using hemodynamic monitoring to direct therapy in shock ? Four types of statements were used: definition, recommendation, best practice and statement of fact.
RESULTS: Forty-four statements were made. The main new statements include: (1) statements on individualizing blood pressure targets; (2) statements on the assessment and prediction of fluid responsiveness; (3) statements on the use of echocardiography and hemodynamic monitoring.
CONCLUSIONS: This consensus provides 44 statements that can be used at the bedside to diagnose, treat and monitor patients with shock
Инфекционная составляющая и иммунопатология при хронических воспалительных заболеваниях слизистой оболочки гастродуоденальной области
Выявлено коинфицирование слизистой оболочки желудочно−кишечного тракта Helicobacter pylori и вирусами группы герпеса у больных хроническим гастритом, язвенной болезнью желудка и двенадцатиперстной кишки. Проведена оценка общих и специфических иммунных реакций организма на указанные инфекционные агенты. Обнаруженные изменения в клеточном и гуморальном звене иммунитета могут свидетельствовать об обусловленном ими системном иммунопатологическом процессе.Co−infection of the gastrointestinal mucosa with Helicobacter pylori and herpes viruses in patients with chronic gastritis, gastric and duodenal ulcer was revealed. General and specific immune reactions of the organism to the above agents were evaluated. The revealed changes in the cellular and humoral immunity can suggest systemic immunopathological process
AMPK:a nutrient and energy sensor that maintains energy homeostasis
AMP-activated protein kinase (AMPK) is a crucial cellular energy sensor. Once activated by falling energy status, it promotes ATP production by increasing the activity or expression of proteins involved in catabolism while conserving ATP by switching off biosynthetic pathways. AMPK also regulates metabolic energy balance at the whole-body level. For example, it mediates the effects of agents acting on the hypothalamus that promote feeding and entrains circadian rhythms of metabolism and feeding behaviour. Finally, recent studies reveal that AMPK conserves ATP levels through the regulation of processes other than metabolism, such as the cell cycle and neuronal membrane excitability
Modeling adsorption in metal-organic frameworks with open metal sites : propane/propylene separations
We present a new approach for modeling adsorption in metal-organic frameworks (MOFs) with unsaturated metal centers and apply it to the challenging propane/propylene separation in copper(II) benzene-1,3,5-tricarboxylate (CuBTC). We obtain information about the specific interactions between olefins and the open metal sites of the MOP using quantum mechanical density functional theory. A proper consideration of all the relevant contributions to the adsorption energy enables us to extract the component that is due to specific attractive interactions between the pi-orbitals of the alkene and the coordinatively unsaturated metal. This component is fitted using a combination of a Morse potential and a power law function and is then included into classical grand canonical Monte Carlo simulations of adsorption. Using this modified potential model, together with a standard Lennard-Jones model, we are able to predict the adsorption of not only propane (where no specific interactions are present), but also of propylene (where specific interactions are dominant). Binary adsorption isotherms for this mixture are in reasonable agreement with ideal adsorbed solution theory predictions. We compare our approach with previous attempts to predict adsorption in MOFs with open metal sites and suggest possible future routes for improving our model
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