Search results for "CAPTURE"

Two- and three-state conical intersections in the electron capture dissociation of disulfides: The importance of multireference calculations

2011

The SS bond cleavage produced upon electron attachment to disulfides was generally assumed to be an adiabatic process because the added electron occupies the σ*(SS) antibonding orbital. This is clearly the case in the parent HSSH compound, but not necessarily in XSSX′ derivatives, where the substituents X and X′ are different. Through the use of MS-CASPT2 calculations, we have shown that the dissociation of the SS two-center-three-electron bond in these asymmetric XSSX′ compounds requires the interaction of at least two states, in order to localize the extra electron in one of the fragments upon dissociation. This is actually the case for the CH3SSNH2 derivative, where the most favorable di…

ETD and ECD Mass Spectrometry Fragmentation for the Characterization of Protein Post Translational Modifications

2012

The introduction of electron capture dissociation (ECD) by McLafferty and co-workers, and further of electron transfer dissociation (ETD), mechanism allows gas-phase fragmentation of multiply charged protein and peptide ions upon capture of a low-energy (<1 eV) electron or electron transfer in a gas phase ion-ion chemistry. The odd-electron species then undergoes rearrangement with subsequent cleavage of N−Cα backbone. Peptide fragmentation can take place inducing the formation of cand ztype fragment ions without loss of the information on the PTM localization. The key to the success of this approach is the selection of intact protein molecular ions and its profound potential for PTM charac…

A full body musculoskeletal model based on flexible multibody simulation approach utilised in bone strain analysis during human locomotion

2011

Load-induced strains applied to bone can stimulate its development and adaptation. In order to quantify the incident strains within the skeleton, in vivo implementation of strain gauges on the surfaces of bone is typically used. However, in vivo strain measurements require invasive methodology that is challenging and limited to certain regions of superficial bones only such as the anterior surface of the tibia. Based on our previous study [Al Nazer et al. (2008) J Biomech. 41:1036-1043], an alternative numerical approach to analyse in vivo strains based on the flexible multibody simulation approach was proposed. The purpose of this study was to extend the idea of using the flexible multibod…

New measurement of the 242Pu(n,γ) cross section at n_TOF

2016

The use of MOX fuel (mixed-oxide fuel made of UO2 and PuO2 ) in nuclear reactors allows substituting a large fraction of the enriched Uranium by Plutonium reprocessed from spent fuel. With the use of such new fuel composition rich in Pu, a better knowledge of the capture and fission cross sections of the Pu isotopes becomes very important. In particular, a new series of cross section evaluations have been recently carried out jointly by the European (JEFF) and United States (ENDF) nuclear data agencies. For the case of 242 Pu, the two only neutron capture time-of-flight measurements available, from 1973 and 1976, are not consistent with each other, which calls for a new time-of flight captu…

Co-evolution between trust in teachers and higher education toward digitally-rich learning environments

2017

Based on a powerful notion that the quality of higher education is crucial for innovation in digital economy and that such quality is subject to a conception of trust in teachers to deliver good education and advancement of information and communication technology (ICT), the dynamism of co-evolution between them was analyzed. Using a unique dataset representing the above system consisting of the rate of trust in teachers providing good education in the context of quality of education and their social status, of the level of higher education and the state of ICT advancement toward digitally-rich learning environments, an empirical numerical analysis of 20 countries was attempted. These count…

A CARBON CONSTRAINED SOCIETY: THE ECONOMICS OF CARBON CAPTURE, UTILIZATION AND STORAGE

Traditionally carbon dioxide (CO2) emissions has been viewed and treated as a “bad” rather than a “good”. This mental model is of little surprise due to a well-established consensus on carbon dioxide as a pollutant constraining the sustainability of economic and social development at a global scale. In the world where so many actors are preoccupied with shifting towards a low- carbon economy the very idea of carbon dioxide being a commodity (literally and not in the form of carbon caps or quotas trade, in which case a “commodity” is in fact the right to emit carbon, which is in its essence a very different concept) might be a big of a statement. However, this idea is not a mere perspective …

Recent Development in Analytical Methods for Identification of Off-Flavour Compounds

1983

The best resolution of individual off-flavour compounds is achieved by glass or quartz capillary gas chromatography. A special two-column system was used by which simultaneous instrumental detection and sniffing (odour desorption) of odorous compounds could be done. The measuring detectors were flame ionization (FID), electron capture (ECD), flame photometric (FPD) and a mass spectrometer (MS). Structural assignments of the odorous substances were done from MS data and verified by model compounds. Before the GC run the sample was collected at the head of the double column using a cold trap device. The sample for analysis was injected in liquid form or, more efficiently, thermally desorbed f…

Microstructural and associated chemical changes during the composting of a high temperature biochar: Mechanisms for nitrate, phosphate and other nutr…

2018

Recent studies have demonstrated the importance of the nutrient status of biochar and soils prior to its inclusion in particular agricultural systems. Pre-treatment of nutrient-reactive biochar, where nutrients are loaded into pores and onto surfaces, gives improved yield outcomes compared to untreated biochar. In this study we have used a wide selection of spectroscopic and microscopic techniques to investigate the mechanisms of nutrient retention in a high temperature wood biochar, which had negative effects on Chenopodium quinoa above ground biomass yield when applied to the system without prior nutrient loading, but positive effects when applied after composting. We have compared non-co…

Two Half-Truths Make a Whole? On Bias in Self-Reports and Tracking Data

2019

The pervasive use of mobile information technologies brings new patterns of media usage, but also challenges to the measurement of media exposure. Researchers wishing to, for example, understand the nature of selective exposure on algorithmically driven platforms need to precisely attribute individuals’ exposure to specific content. Prior research has used tracking data to show that survey-based self-reports of media exposure are critically unreliable. So far, however, little effort has been invested into assessing the specific biases of tracking methods themselves. Using data from a multimethod study, we show that tracking data from mobile devices is linked to systematic distortions in sel…

Capture Aware Sequential Waterfilling for LoraWAN Adaptive Data Rate

2020

LoRaWAN (Long Range Wide Area Network) is emerging as an attractive network infrastructure for ultra low power Internet of Things devices. Even if the technology itself is quite mature and specified, the currently deployed wireless resource allocation strategies are still coarse and based on rough heuristics. This paper proposes an innovative "sequential waterfilling" strategy for assigning Spreading Factors (SF) to End-Devices (ED). Our design relies on three complementary approaches: i) equalize the Time-on-Air of the packets transmitted by the system's EDs in each spreading factor's group; ii) balance the spreading factors across multiple access gateways, and iii) keep into account the c…