Size-exclusion chromatographic NMR under HR-MAS

The addition of stationary phases or sample modifiers can be used to modify the separation achievable in the diffusion domain of diffusion NMR experiments or provide information on the nature of the analyte–sample modifier interaction. Unfortunately, the addition of insoluble chromatographic stationary phases can lead to line broadening and degradation in spectral resolution, largely because of differences in magnetic susceptibility between the sample and the stationary phase. High-resolution magic angle spinning (HR-MAS) techniques can be used to remove this broadening. Here, we attempt the application of HR-MAS to size-exclusion chromatographic NMR with limited success. Observed diffusion coefficients for polymer molecular weight reference standards are shown to be larger than those obtained on static samples. Further investigation reveals that under HR-MAS it is possible to obtain reasonably accurate estimates of diffusion coefficients, using either full rotor synchronisation or sophisticated pulse sequences. The requirement for restricting the sample to the centre of the MAS rotor to ensure homogeneous magnetic and RF fields is also tested

L’impact des mécanismes d’incitation à la réduction des émissions polluantes du secteur énergétique, sur la performance des investissements entrants au Maroc : une analyse empirique

In a global context marked by ecological crisis and economic challenges, the issue of attracting investment to stimulate economic growth often comes up against environmental concerns. This duality between attracting investment and ensuring sustainable resource management raises a complex paradox that requires in-depth analysis. It is in this complex context that this article takes place, the main objective of which is to study the links that exist between the performance of incoming investments in Morocco and the implementation of incentive mechanisms aimed at reducing carbon emissions. carbon dioxide (CO2), greenhouse gases (GHG), and the environmental tax. The empirical study is based on the ARDL (AutoRegressive Distributed Lag) econometric methodology. This method of analyzing time series makes it possible to explore the relationships between the different variables. Specifically, the study examines the short-term and long-term effects of environmental tax, CO2 and GHG emissions on inward investment performance. Based on the results obtained, the article also aims to propose solutions, to raise the paradox between the attractiveness of investments and the preservation of the ecosystem. Despite the significant relationships brought to light by the analysis, showing how incentives to reduce polluting emissions and the implementation of the environmental tax generate positive effects on the performance of investments, the conclusions insinuate that persevering in the transition towards greener energy practices remains essential. It is not only a question of strengthening financial incentives in favor of environmentally friendly projects, but also of promoting innovative financing mechanisms to stimulate the attractiveness of investments in this sector.   Keywords: Polluting emissions, Inward investment performance index, Environmental tax, Greenhouse gases Classification JEL : C22, O13, K32, F21 Paper type: Empirical researchDans un contexte mondial marqué par la crise écologique et les défis économiques, la question d'attirer les investissements pour stimuler la croissance économique se heurte souvent à la préoccupation environnementale. Cette dualité entre attirer les investissements et assurer une gestion durable des ressources soulève un paradoxe complexe qui nécessite une analyse approfondie. C'est dans ce contexte complexe que prend place le présent article dont l’objectif principal est d'étudier les liens qui existent entre la performance des investissements entrants au Maroc et la mise en œuvre de mécanismes d'incitation visant la réduction des émissions de dioxyde de carbone (CO2), de gaz à effet de serre (GES), et de la taxe environnementale. L’étude empirique se base sur la méthodologie économétrique ARDL (AutoRegressive Distributed Lag). Cette méthode d'analyse des séries temporelles, permet d'explorer les relations entre les différentes variables. Plus précisément, l'étude examine les effets à court et à long terme de la taxe environnementale, des émissions de CO2 et de GES sur la performance des investissements entrants. En se basant sur les résultats obtenus, l’article vise également à proposer des solutions, pour soulever le paradoxe entre l'attractivité des investissements et la préservation de l'écosystème. Malgré les relations significatives mises en lumière par l'analyse, montrant comment les incitations à la réduction des émissions polluantes et la mise en œuvre de la taxe environnementale engendrent des effets positifs sur la performance des investissements, les conclusions insinuent que persévérer dans la transition vers des pratiques énergétiques plus vertes demeure essentiel. Il s'agit non seulement de renforcer les incitations financières en faveur des projets respectueux de l'environnement, mais également de promouvoir des mécanismes de financement innovants pour stimuler l'attractivité des investissements dans ce secteur.   Mots clés : Emissions polluantes, Indice de performance des investissements entrants, Taxe environnementale, Gaz à effet de serre Classification JEL : C22, O13, K32, F21 Type de l’article : Recherche appliqué

Les innovations vertes comme levier pour une dynamique entrepreneuriale durable

This research raises the question of promoting green innovations and their capacities to exert an impact in favor of a sustainable entrepreneurial dynamic, in a context marked by a global economic crisis, coupled with an ecological and health crisis. The attractiveness of territories and the promotion of investments are more relevant than ever, as countries seek to attract businesses as much as possible and avoid relocations. However, quantitative and traditional instruments, based mainly on ecological standards or quotas, exert pressure on the entrepreneurial fabric, and can have harmful aspects of the productivity, competitiveness and returns of companies, which, at the base seek territories with lax and less expensive standards. In such a context thus brings the world into a very fierce territorial competition. In addition, green innovations and entrepreneurial dynamics, although they appear to be two antagonistic concepts, and very different at first glance, nevertheless constitute two notions inherent in life in general and in a new phase of a sustainable economic dynamic in a particular way. . Something that urges us to rethink environmental policy, with a new rehabilitation of the role of government bodies, which are blocked by the negative consequences of the quantitative instruments put in place by government bodies. While the integration of private actors is now crucial, both in terms of the invention of clean technologies, and in terms of their financing. For these reasons, bringing the two concepts closer together: incentives for green innovations and entrepreneurial promotion are necessary first. While emphasizing the different configurations by the market as well as the state. Subsequently, analyzing the various environmental, entrepreneurial and social challenges in the literature will make it possible to rethink the issue of environmental policy rehabilitation, in order to guarantee more effective management of the environment and create a new sustainable entrepreneurial dynamic.La présente recherche soulève la question de promotion des innovations vertes et leurs capacités à exercer un impact en faveur d’une dynamique entrepreneuriale durable, ceci dans un contexte marqué par une crise économique mondiale, doublée d’une crise écologique et sanitaire. L’attractivité des territoires et la promotion des investissements est plus que jamais d’actualité, car les pays cherchent à attirer au maximum les entreprises et à éviter les délocalisations. Cependant, les instruments quantitatifs et traditionnels, basée principalement sur les normes écologiques ou les quotas, exercent des pressions sur le tissu entrepreneurial, et peuvent avoir des aspects néfastes sur la productivité, la compétitivité et les rendements des entreprises, qui à la base cherchent des territoires à normes laxistes et moins couteuses. Un contexte pareil, fait ainsi rentrer le monde dans une concurrence territoriale très acharnée. Par ailleurs les innovations vertes et la dynamique entrepreneuriale, bien qu’ils paraissent deux concepts antagonistes, et très différents à première vue, constituent pourtant deux notions inhérentes à la vie en générale et à une nouvelle phase d’une dynamique économique durable de manière particulière. Chose qui invite vivement à repenser la politique environnementale, avec une nouvelle réhabilitation du rôle des instances gouvernementales qui se trouvent bloquées devant les conséquences négatives des instruments quantitatifs mises en place par les instances gouvernementales. Alors que, l’intégration des acteurs privés s’avère aujourd’hui crucial, tant  en termes d’invention de technologies propres, qu’au niveau de leurs financements. Pour ces raisons, rapprocher les deux concepts: les incitations aux innovations vertes et la promotion entrepreneuriale s’imposent dans un premier temps. Tout en mettant l’accent sur  les différentes configurations par le marché aussi bien que l’État. Par la suite, analysez les différents défis environnementaux, entrepreneuriaux et sociaux dans la littérature, permettra de repenser la question de réhabilitation de la politique environnementale, afin de garantir une prise en charge plus efficace de l’environnement et créer une nouvelle dynamique entrepreneuriale durable

Towards real-time metabolic profiling of a biopsy specimen during a surgical operation by 1H high resolution magic angle spinning nuclear magnetic resonance: a case report

<p>Abstract</p> <p>Introduction</p> <p>Providing information on cancerous tissue samples during a surgical operation can help surgeons delineate the limits of a tumoral invasion more reliably. Here, we describe the use of metabolic profiling of a colon biopsy specimen by high resolution magic angle spinning nuclear magnetic resonance spectroscopy to evaluate tumoral invasion during a simulated surgical operation.</p> <p>Case presentation</p> <p>Biopsy specimens (n = 9) originating from the excised right colon of a 66-year-old Caucasian women with an adenocarcinoma were automatically analyzed using a previously built statistical model.</p> <p>Conclusions</p> <p>Metabolic profiling results were in full agreement with those of a histopathological analysis. The time-response of the technique is sufficiently fast for it to be used effectively during a real operation (17 min/sample). Metabolic profiling has the potential to become a method to rapidly characterize cancerous biopsies in the operation theater.</p

Metabolomic Characterization of Ovarian Epithelial Carcinomas by HRMAS-NMR Spectroscopy

Objectives. The objectives of the present study are to determine if a metabolomic study by HRMAS-NMR can (i) discriminate between different histological types of epithelial ovarian carcinomas and healthy ovarian tissue, (ii) generate statistical models capable of classifying borderline tumors and (iii) establish a potential relationship with patient's survival or response to chemotherapy. Methods. 36 human epithelial ovarian tumor biopsies and 3 healthy ovarian tissues were studied using 1H HRMAS NMR spectroscopy and multivariate statistical analysis. Results. The results presented in this study demonstrate that the three histological types of epithelial ovarian carcinomas present an effective metabolic pattern difference. Furthermore, a metabolic signature specific of serous (N-acetyl-aspartate) and mucinous (N-acetyl-lysine) carcinomas was found. The statistical models generated in this study are able to predict borderline tumors characterized by an intermediate metabolic pattern similar to the normal ovarian tissue. Finally and importantly, the statistical model of serous carcinomas provided good predictions of both patient's survival rates and the patient's response to chemotherapy. Conclusions. Despite the small number of samples used in this study, the results indicate that metabolomic analysis of intact tissues by HRMAS-NMR is a promising technique which might be applicable to the therapeutic management of patients

High-resolution magic angle spinning 1H nuclear magnetic resonance spectroscopy metabolomics of hyperfunctioning parathyroid glands

Background Primary hyperparathyroidism (PHPT) may be related to a single gland disease or multiglandular disease, which requires specific treatments. At present, an operation is the only curative treatment for PHPT. Currently, there are no biomarkers available to identify these 2 entities (single vs. multiple gland disease). The aims of the present study were to compare (1) the tissue metabolomics profiles between PHPT and renal hyperparathyroidism (secondary and tertiary) and (2) single gland disease with multiglandular disease in PHPT using metabolomics analysis. Methods The method used was 1H high-resolution magic angle spinning nuclear magnetic resonance spectroscopy. Forty-three samples from 32 patients suffering from hyperparathyroidism were included in this study. Results Significant differences in the metabolomics profile were assessed according to PHPT and renal hyperparathyroidism. A bicomponent orthogonal partial least square-discriminant analysis showed a clear distinction between PHPT and renal hyperparathyroidism (R2Y = 0.85, Q2 = 0.63). Interestingly, the model also distinguished single gland disease from multiglandular disease (R2Y = 0.96, Q2 = 0.55). A network analysis was also performed using the Algorithm to Determine Expected Metabolite Level Alterations Using Mutual Information (ADEMA). Single gland disease was accurately predicted by ADEMA and was associated with higher levels of phosphorylcholine, choline, glycerophosphocholine, fumarate, succinate, lactate, glucose, glutamine, and ascorbate compared with multiglandular disease. Conclusion This study shows for the first time that 1H high-resolution magic angle spinning nuclear magnetic resonance spectroscopy is a reliable and fast technique to distinguish single gland disease from multiglandular disease in patients with PHPT. The potential use of this method as an intraoperative tool requires specific further studies. © 2016 Elsevier Inc

A new specific succinate-glutamate metabolomic hallmark in SDHx-related paragangliomas

Paragangliomas (PGLs) are frequently associated with germline mutations in genes involved in energy metabolism. The purpose of the present study was to assess whether the tumor metabolomic profile of patients with hereditary and apparently sporadic PGLs enables the distinction of different subtypes of tumors. Twenty-eight unrelated patients with a histological diagnosis of PGLs were included in the present study. Twelve had germline mutations in SDHx genes (5 SDHB, 7 SDHD), 6 VHL, and 10 were apparently sporadic. Intact tumor samples from these patients (one per patient) were evaluated with (1)H high-resolution magic angle spinning (HRMAS) NMR spectroscopy. SDHx-related tumors were characterized by an increase in succinate levels in comparison to other tumor subtypes (p = 0.0001 vs VHL and p = 0.000003 vs apparently sporadic). Furthermore, we found significantly lower values of glutamate in SDHx-related tumors compared to other subtypes (p = 0.0007 vs VHL and p = 0.003 vs apparently sporadic). Moreover, SDHx-tumors also exhibited lower values of ATP/ADP/AMP (p = 0.01) compared to VHL. VHL tumors were found to have the highest values of glutathione (GSH) compared to other tumors. Based on 4 metabolites (succinate, glutamate, GSH, and ATP/ADP/AMP), tumors were accurately distinguished from the other ones on both 3- and 2-class PLS-DA models. The present study shows that HRMAS NMR spectroscopy is a very promising method for investigating the metabolomic profile of various PGLs. The present data suggest the existence of a specific succinate-glutamate hallmark of SDHx PGLs. The relevance of such a metabolomic hallmark is expected to be very useful in designing novel treatment options as well as improving the diagnosis and follow-up of these tumors, including metastatic ones

Logiciels pour l'analyse et l'exploitation des meusres de relaxation magnetique nucleaire. Etude approfondie des phenomenes de relaxation croisee dans un systeme de deux spin 1/2

SIGLEINIST T 74320 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

ASPECTS EXPERIMENTAUX ET METHODOLOGIQUES DE LA TECHNIQUE RMN HAUTE RESOLUTION A L'ANGLE MAGIQUES (HRMAS). APPLICATIONS A DES COMPOSES GREFFES SUR DIFFERENTES RESINES

CETTE THESE DECRIT QUELQUES ASPECTS EXPERIMENTAUX ET METHODOLOGIQUES DE LA TECHNIQUE RMN HAUTE RESOLUTION A L'ANGLE MAGIQUE (HRMAS) APPLIQUEE A DES COMPOSES GREFFES SUR DES RESINES. NOUS MONTRONS NOTAMMENT QUE L'ELARGISSEMENT DES RAIES DE LA MOLECULE GREFFEE PROVIENT DES CYCLES AROMATIQUES DES RESINES DONT L'ANISOTROPIE DE SUSCEPTIBILITE MAGNETIQUE N'EST PAS MOYENNEE PAR LA ROTATION A L'ANGLE MAGIQUE. L'UTILISATION DE RESINES NE CONTENANT PAS DE CYCLES AROMATIQUES, COMME LES RESINES PEGA ET POEPOP, PERMET D'OBTENIR UNE RESOLUTION QUASI-LIQUIDE. GRACE A CES RESINES, NOUS AVONS PU MESURER PRECISEMENT L'EXCES ENANTIOMERIQUE D'UN ECHANTILLON CONTENANT 4 DIASTEREOISOMERES D'UNE DICETOPIPERAZINE DIRECTEMENT SUR UN SPECTRE MONODIMENSIONNEL. PAR AILLEURS, CETTE RESINE POEPOP A PERMIS D'IDENTIFIER POUR LA PREMIERE FOIS UNE HELICE SUR LE PEPTIDE 141-160 DU VIRUS FMDV. DANS CETTE ETUDE, NOUS AVONS EGALEMENT MONTRE QUE LA STRUCTURE D'UN PEPTIDE EN SOLUTION ETAIT PRESERVEE LORSQU'IL ETAIT GREFFE SUR UNE RESINE. D'UN POINT DE VUE PLUS METHODOLOGIQUE, NOUS AVONS MONTRE QUE LES INHOMOGENEITES RADIALES DU CHAMP RADIOFREQUENCE POUVAIENT ETRE A L'ORIGINE DE LA DESTRUCTION COMPLETE DE L'AIMANTATION PENDANT DES EXPERIENCES DE TYPE TOCSY ENREGISTREES EN ROTATION A L'ANGLE MAGIQUE. ENFIN, NOUS AVONS MONTRE QU'IL ETAIT POSSIBLE DE DETECTER DES INTERACTIONS DIPOLAIRES RESIDUELLES 1H- 1H EN HRMAS EN UTILISANT DES EXPERIENCES CLASSIQUES DE RECOUPLAGE DIPOLAIRE. CES INTERACTIONS DIPOLAIRES RESIDUELLES PERMETTENT D'OBTENIR DES INFORMATIONS STRUCTURALES A LONGUE DISTANCE.STRASBOURG-Sc. et Techniques (674822102) / SudocSudocFranceF

L’impact des mécanismes d’incitation à la réduction des émissions polluantes du secteur énergétique, sur la performance des investissements entrants au Maroc : une analyse empirique

In a global context marked by ecological crisis and economic challenges, the issue of attracting investment to stimulate economic growth often comes up against environmental concerns. This duality between attracting investment and ensuring sustainable resource management raises a complex paradox that requires in-depth analysis. It is in this complex context that this article takes place, the main objective of which is to study the links that exist between the performance of incoming investments in Morocco and the implementation of incentive mechanisms aimed at reducing carbon emissions. carbon dioxide (CO2), greenhouse gases (GHG), and the environmental tax. The empirical study is based on the ARDL (AutoRegressive Distributed Lag) econometric methodology. This method of analyzing time series makes it possible to explore the relationships between the different variables. Specifically, the study examines the short-term and long-term effects of environmental tax, CO2 and GHG emissions on inward investment performance. Based on the results obtained, the article also aims to propose solutions, to raise the paradox between the attractiveness of investments and the preservation of the ecosystem. Despite the significant relationships brought to light by the analysis, showing how incentives to reduce polluting emissions and the implementation of the environmental tax generate positive effects on the performance of investments, the conclusions insinuate that persevering in the transition towards greener energy practices remains essential. It is not only a question of strengthening financial incentives in favor of environmentally friendly projects, but also of promoting innovative financing mechanisms to stimulate the attractiveness of investments in this sector. &nbsp; Keywords: Polluting emissions, Inward investment performance index, Environmental tax, Greenhouse gases Classification JEL : C22, O13, K32, F21 Paper type: Empirical researchDans un contexte mondial marqué par la crise écologique et les défis économiques, la question d'attirer les investissements pour stimuler la croissance économique se heurte souvent à la préoccupation environnementale. Cette dualité entre attirer les investissements et assurer une gestion durable des ressources soulève un paradoxe complexe qui nécessite une analyse approfondie. C'est dans ce contexte complexe que prend place le présent article dont l’objectif principal est d'étudier les liens qui existent entre la performance des investissements entrants au Maroc et la mise en œuvre de mécanismes d'incitation visant la réduction des émissions de dioxyde de carbone (CO2), de gaz à effet de serre (GES), et de la taxe environnementale. L’étude empirique se base sur la méthodologie économétrique ARDL (AutoRegressive Distributed Lag). Cette méthode d'analyse des séries temporelles, permet d'explorer les relations entre les différentes variables. Plus précisément, l'étude examine les effets à court et à long terme de la taxe environnementale, des émissions de CO2 et de GES sur la performance des investissements entrants. En se basant sur les résultats obtenus, l’article vise également à proposer des solutions, pour soulever le paradoxe entre l'attractivité des investissements et la préservation de l'écosystème. Malgré les relations significatives mises en lumière par l'analyse, montrant comment les incitations à la réduction des émissions polluantes et la mise en œuvre de la taxe environnementale engendrent des effets positifs sur la performance des investissements, les conclusions insinuent que persévérer dans la transition vers des pratiques énergétiques plus vertes demeure essentiel. Il s'agit non seulement de renforcer les incitations financières en faveur des projets respectueux de l'environnement, mais également de promouvoir des mécanismes de financement innovants pour stimuler l'attractivité des investissements dans ce secteur. &nbsp; Mots clés&nbsp;: Emissions polluantes, Indice de performance des investissements entrants, Taxe environnementale, Gaz à effet de serre Classification JEL : C22, O13, K32, F21 Type de l’article : Recherche appliqué