Desorption/Ionization on self-Assembled Monolayer Surface (DIAMS) Evaluation of a New Matrix-Free Laser Desorption/Ionization method

Date du colloque&nbsp;: 06/2008</p

New proaporphines from the bark of Phoebe scortechinii

The phytochemical study of the bark of Malaysian Phoebe scortechinii (Lauraceae) has resulted in the isolation and identification of two new proaporphine alkaloids; (+)-scortechiniine A (1) and (+)-scortechiniine B (2) together with two known proaporphines; (−)-hexahydromecambrine A (3), (−)-norhexahydromecambrine A (4), and one aporphine; norboldine (5). Structural elucidations of these alkaloids were performed using spectroscopic methods especially 1D and 2D 1H and 13C NMR

Sagebrush landscape: Upper Gunnison River Basin, Colorado Social-Ecological Climate Resilience Project

Prepared with: The Gunnison Climate Working Group and Stakeholders in Gunnison, Colorado for: the North Central Climate Science Center, Ft. Collins, Colorado.April 30, 2017.Includes bibliographical references.Utilizing climate stories to understand the social and ecological impacts to the sagebrush landscape, the team worked with stakeholders to develop three overarching landscape‐scale adaptation strategies. Each of the strategies has a suite of potential actions required to reach a desired future condition. The three key strategies are: 1) identify and protect climate refugia sites (persistent areas), 2) maintain or enhance the resilience of the climate refugia sites, and 3) accept, assist and allow for transformation in non‐climate refugia sites. If adopted by the local community, including land managers and landowners, the framework and strategies resulting from this project can help to reduce the adverse impacts of climate change, allowing for a more sustainable human and natural landscape

What difference does ("good") HRM make?

The importance of human resources management (HRM) to the success or failure of health system performance has, until recently, been generally overlooked. In recent years it has been increasingly recognised that getting HR policy and management "right" has to be at the core of any sustainable solution to health system performance. In comparison to the evidence base on health care reform-related issues of health system finance and appropriate purchaser/provider incentive structures, there is very limited information on the HRM dimension or its impact. Despite the limited, but growing, evidence base on the impact of HRM on organisational performance in other sectors, there have been relatively few attempts to assess the implications of this evidence for the health sector. This paper examines this broader evidence base on HRM in other sectors and examines some of the underlying issues related to "good" HRM in the health sector. The paper considers how human resource management (HRM) has been defined and evaluated in other sectors. Essentially there are two sub-themes: how have HRM interventions been defined? and how have the effects of these interventions been measured in order to identify which interventions are most effective? In other words, what is "good" HRM? The paper argues that it is not only the organisational context that differentiates the health sector from many other sectors, in terms of HRM. Many of the measures of organisational performance are also unique. "Performance" in the health sector can be fully assessed only by means of indicators that are sector-specific. These can focus on measures of clinical activity or workload (e.g. staff per occupied bed, or patient acuity measures), on measures of output (e.g. number of patients treated) or, less frequently, on measures of outcome (e.g. mortality rates or rate of post-surgery complications). The paper also stresses the need for a "fit" between the HRM approach and the organisational characteristics, context and priorities, and for recognition that so-called "bundles" of linked and coordinated HRM interventions will be more likely to achieve sustained improvements in organisational performance than single or uncoordinated interventions

Evaluation of a new matrix-free laser desorption/ionization method through statistic studies: comparison of the DIAMS (desorption/ionization on self-assembled monolayer surface) method with the MALDI and TGFA-LDI techniques

This work demonstrates that the desorption/ionization on self-assembled monolayer surface (DIAMS) mass spectrometry, a recent matrix-free laser desorption/ionization (LDI) method based on an organic target plate, is as statistically repeatable and reproducible as matrix assisted laser desorption ionization (MALDI) and thin gold film-assisted laser desorption/ionization (TGFA-LDI) mass spectrometries. On lipophilic DIAMS of target plates with a mixture of glycerides, repeatability/reproducibility has been estimated at 15 and 30% and the relative detection limit has been evaluated at 0.3 and 3 pmol, with and without NaI respectively. Salicylic acid and its d6-isomer analysis confirm the applicability of the DIAMS method in the detection of compounds of low molecular weight

Quantum Hall Effects in Graphene-Based Two-Dimensional Electron Systems

In this article we review the quantum Hall physics of graphene based two-dimensional electron systems, with a special focus on recent experimental and theoretical developments. We explain why graphene and bilayer graphene can be viewed respectively as J=1 and J=2 chiral two-dimensional electron gases (C2DEGs), and why this property frames their quantum Hall physics. The current status of experimental and theoretical work on the role of electron-electron interactions is reviewed at length with an emphasis on unresolved issues in the field, including assessing the role of disorder in current experimental results. Special attention is given to the interesting low magnetic field limit and to the relationship between quantum Hall effects and the spontaneous anomalous Hall effects that might occur in bilayer graphene systems in the absence of a magnetic field

Desorption/ionization on self-assembled monolayer surfaces (DIAMS): a new matrix-free laser desorption/ionization promising for the analysis of vegetal extracts

Rapid analysis of small molecular weight compounds is one of the most widespread applications of mass spectrometry. The high throughput analyses of vegetal extracts are relatively difficult to perform in MALDI mass spectrometry, since preparation of the sample involves the co-crystallization of the matrix with the analyte. Moreover irradiation of the matrix ion produces many low-m/z vs high-intensity ions preventing the detection of low molecular weight molecules such as secondary metabolites.Our work aims at developing a matrix free alternative to MALDI analysis by the means of an original desorption/ionization on self-assembled monolayers surfaces (DIAMS) technique. We have focused our attention on a monolayer constituted by a 2,2\u27-bithiophene 5-substituted by an alkylthio linked to the gold surface [1]. With the example of salicylate derivatives, we show that the DIAMS method is suitable to the detection and quantification of the low molecular weight compounds. Indeed, the technique is as statistically repeatable and reproducible as other mass spectrometries [2]. This DIAMS method could be suitable to the qualitative and quantitative studies of polar and apolar vegetal extracts without any preliminary chromatographic resolution