1,279 research outputs found
Output-based allocations in pollution markets with uncertainty and self-selection
We study pollution permit markets in which a fraction of permits are allocated to firms based on their output. Output-based allocations, which are receiving increasing attention in the design of carbon markets around the world (e.g., Europe, California, New Zealand), are shown to be optimal under demand and supply volatility despite the output distortions they may create. In a market that covers multiple sectors, the optimal design combines auctioned permits with output-based allocations that are specific to each sector and increasing in its volatility. When firms are better informed about the latter or must self select, the regulator resort to some free (i.e., lump-sum) allocations to sort firms out. Numerical exercises illustrate the policy relevance of our results: the gains from considering output-based allocations can be substantial
Utilisation et Modification de la b-cyclodextrine et de système mono-osidique en angiogenèse
La croissance tumorale et le développement des métastases sont dépendants de l'angiogenèse et reposent sur un switch angiogénique . Dès lors, inhiber l'angiogenèse apparaît très naturellement comme une nouvelle stratégie thérapeutique anti-cancéreuse qui consiste tout simplement à affamer une tumeur en la privant de sa vascularisation. L'angiogenèse est un processus physiologique qui fait intervenir de nombreux récepteurs, dont le récepteur du mannose-6-Phosphate ou Insulin Growth Factor II (RM6P/IGF-II). Des travaux antérieurs effectués au laboratoire ont montré que des molécules analogues du M6P sont des effecteurs d'angiogenèse mais qu'au cours de leur administration, ces composés sont facilement éliminés car trop hydrophiles. Afin d'obtenir des analogues du M6P plus lipophiles, nous avons remplacé le méthyle en position anomère par un pentyle. Par ailleurs, pour étudier l'effet cluster et la protection par une molécule enveloppante, une nouvelle famille de composés dérivant de la b-Cyclodextrine a été préparée. Des dérivés originaux, présentant des fonctions phosphates et azido, ainsi qu'une couronne de mannose ont été synthétisés.Tumor growth and development of metastasis are dependent on angiogenesis and based on an angiogenic switch . Therefore, to inhibit angiogenesis appears quite evidently as a new anticancer strategy which corresponds simply to starve a tumor by depriving its vascularisation. Angiogenesis is a physiological process that involves many receptors, including the RM6P/IGF-2. Previous work conducted in the laboratory has shown that analogues of M6P are effectors of angiogenesis but during administration, these compounds are easily removed due to their hydrophilicity. To increase the lipophilicity of the M6P analogues, we have replaced the methyl group at the anomeric position by a pentyl group. Also to study the cluster effect and the protective transport of molecules, a new family of compounds derived from b-cyclodextrin were prepared. Original derivatives, having azido and phosphate functions, and a crown made of mannose were synthesised.MONTPELLIER-Ecole Nat.Chimie (341722204) / SudocSudocFranceF
European intensive care physicians’ experience of infections due to antibiotic-resistant bacteria
Background Antimicrobial resistance (AMR) compromises the treatment of patients with serious infections in intensive care units (ICUs), and intensive care physicians are increasingly facing patients with bacterial infections with limited or no adequate therapeutic options. A survey was conducted to assess the intensive care physicians' perception of the AMR situation in the European Union/European Economic Area (EU/EEA). Methods Between May and July 2017, physicians working in European ICUs were invited to complete an online questionnaire hosted by the European Society of Intensive Care Medicine. The survey included 20 questions on hospital and ICU characteristics, frequency of infections with multidrug-resistant (MDR) bacteria and relevance of AMR in the respondent's ICU, management of antimicrobial treatment as well as the use of last-line antibiotics in the six months preceding the survey. For the analysis of regional differences, EU/EEA countries were grouped into the four sub-regions of Eastern, Northern, Southern and Western Europe. Results Overall, 1062 responses from four European sub-regions were analysed. Infections with MDR bacteria in their ICU were rated as a major problem by 257 (24.2%), moderate problem by 360 (33.9%) and minor problem by 391 (36.8%) respondents. Third-generation cephalosporin-resistant Enterobacteriaceae were the most frequently encountered MDR bacteria followed by, in order of decreasing frequency, meticillin-resistant Staphylococcus aureus, carbapenem-resistant Enterobacteriaceae, carbapenem-resistant Pseudomonas aeruginosa and vancomycin-resistant enterococci. Perception of the relevance of the AMR problem and the frequency of specific MDR bacteria varied by European sub-region. Bacteria resistant to all or almost all available antibiotics were encountered by 132 (12.4%) respondents. Many physicians reported not having access to specific last-line antibiotics. Conclusions The percentage of European ICU physicians perceiving AMR as a substantial problem in their ICU is high with variation by sub-region in line with epidemiological studies. The reports of bacteria resistant to almost all available antibiotics and the limited availability of last-line antibiotics in ICUs in the EU/EEA are of concern
Synthesis of rhodamine B ?€" benzenesulfonamide conjugates and their inhibitory activity against human ?- and bacterial/fungal ?-carbonic anhydrases
n/
El oro de Guarrazar
Se presentan los primeros resultados analĂticos del oro del Tesoro visigodo
de Guarra/ar (Guadamur. Toledo) enmarcado en un proyecto para caracterizar
estas producciones orfebres y su nivel tecnolĂłgico. AsĂ mismo, se pretende acla
rar ciertos aspectos sobre su estado actual, como las asociaciones entre materia
les o la identificación de partes originales y reconstruidas. Los análisis de com
posiciĂłn se han realizado mediante PIXE
Ionization, intrinsic basicity, and intrinsic acidity of unsaturated diols of astrochemical interest: 1,1- and 1,2-ethenediol: A theoretical survey
The structure, stability, and bonding characteristics of 1,1- and 1,2-ethenediol, their
radical cations, and their protonated and deprotonated species were investigated
using high-level ab initio G4 calculations. The electron density of all the neutral and
charged systems investigated was analyzed using the QTAIM, ELF, and NBO
approaches. The vertical ionization potential (IP) of the five stable tautomers of
1,2-ethenediol and the two stable tautomers of 1,1-ethenediol go from 11.81 to
12.27 eV, whereas the adiabatic ones go from 11.00 to 11.72 eV. The adiabatic ionization leads to a significant charge delocalization along the O-C-C-O skeleton. The
most stable protonated form of (Z)-1,2-ethenediol can be reached by the protonation
of both the anti-anti and the syn-anti conformers, whereas the most stable deprotonated form arises only from the syn-anti one. Both charged species are
extra-stabilized by the formation of an O-H O intramolecular hydrogen bond (IHB)
which is not found in the neutral system. (Z)-1,2-ethenediol is predicted to be less
stable, less basic, and more acidic than its cis-glycolaldehyde isomer. The most stable
protonated species of (E)-1,2-ethenediol comes from its syn-syn conformer, although
the anti-anti conformer is the most basic one. Contrarily, the three conformers yield a
common deprotonated species, so their acidity follows exactly their relative stability.
Again, the (E)-1,2-ethenediol is predicted to be less stable, less basic, and more acidic
than its trans-glycolaldehyde isomer. Neither the neutral nor the protonated or the
deprotonated forms of 1,1-ethenediol show the formation of any O-H O IHB. The
most stable protonated species is formed by the protonation of any of the two tautomers, but the most stable deprotonated form arises exclusively from the syn-anti neutral conformer. The conformers of 1,1-ethenediol are much less stable and
significantly less basic than their isomer, acetic acid, and only slightly more acidicThis work was carried out with financial support from the projects
PID2021-125207NB-C31 and PID2019-110091GB-I00 of the Ministerio de Ciencia, Innovacion y Universidades of Spain (MICINN) and the
project Y2020/EMT-6290 (PRIES-CM) of the Comunidad de Madri
Photon momentum anisotropies from the late stages of relativistic heavy-ion collisions
The photon emission from the late stages of the dynamical evolution of
heavy-ion reactions at the highest RHIC and LHC energies is investigated. A
comparison between a calculation from hadronic rates from a fluid dynamic
evolution down to temperatures of 120 MeV and a full non-equilibrium hadronic
transport approach is performed. The photon yields are very similar in both
cases while the elliptic flow is slightly smaller in the non-equilibrium
scenario. This study is important, since it is crucial to apply the same
dynamical evolution model for hadronic and electromagnetic observables.Comment: 6 pages, 4 figures, accepted in PoS for Hard Probes 202
Electric sampling of soot particles in spreading non-premixed flames: methodology and influence of gravity
Finer strategies of spacecraft fire mitigation require more experimental data related to fire detection. Fire detection systems developed on Earth rely massively on the optical detection of soot particles, which are present in the smoke. To detect the fire correctly, it is thus important to know how the optical properties of these particles are affected in reduced gravity. With different transport processes and increased residence time, soot in reduced gravity can be different from those produced at normal gravity. As their optical properties are related to their morphological properties, a better understanding about the evolution of soot particle morphology in flames under microgravity conditions is required. Within this context, a novel technique of soot sampling using electric field is applied to a spreading non-premixed flame at normal and micro-gravity. The soot particles sampled are observed subsequently under Transmission Electron Microscopy (TEM). Density, soot particle projected area, radius of gyration, fractal dimension, and primary particle size are extracted and the influence of gravity is investigated with the evolution of these morphological properties within the flame. Though the present study cannot be conclusive in itself, the similarity between the evolution of the optical density measured throughout the flame just before the electric perturbation required by the sampling technique and the evolution of the amount of soot deposited due to the electric perturbation along the sampling plates supports the future works that need to be devoted to further assess the consistency of the technique
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