196,076 research outputs found
SlackCheck: A Linux Kernel Module to Verify Temporal Properties of a Task Schedule
No full textThe Linux Kernel offers several scheduling classes. From SCHED_DEADLINE down to SCHED_FIFO, SCHED_RR and SCHED_OTHER, the scheduling classes can provide different responsiveness to very diverse user workloads. Still, Linux does not offer any mechanism to take some action upon the violation of temporal constraints at runtime. The lack of such a feature is also due to the difficulty of extending the established notion of deadline to workloads which are not releasing periodic/sporadic jobs.
Exploiting the notion of supply functions for any resource schedule, we implemented SlackCheck, a kernel module which is capable to verify at runtime if a given task is assigned a desired amount of resource or not. SlackCheck adds a constant-time check at every scheduling decision and leverages the recent availability of a Runtime Verification engine in the kernel
Effect of addition of enzymes to the diet on utilization of protein and energy by rabbits
No full textPerspectives of Gas Phase Ion Chemistry: Spectroscopy and Modeling
No full textThe study of ions in the gas phase has a long history and has involved both chemists and physicists. The interplay of their competences with the use of very sophisticated commercial and/or homemade instrumentations and theoretical models has improved the knowledge of thermodynamics and kinetics of many chemical reactions, even if still many stages of these processes need to be fully understood. The new technologies and the novel free-electron laser facilities based on plasma acceleration open new opportunities to investigate the chemical reactions in some unrevealed fundamental aspects. The synchrotron light source can be put beside the FELs, and by mass spectrometric techniques and spectroscopies coupled with versatile ion sources it is possible to really change the state of the art of the ion chemistry in different areas such as atmospheric and astro chemistry, plasma chemistry, biophysics, and interstellar medium (ISM). In this manuscript we review the works performed by a joint combination of the experimental studies of ion–molecule reactions with synchrotron radiation and theoretical models adapted and developed to the experimental evidence. The review concludes with the perspectives of ion–molecule reactions by using FEL instrumentations as well as pump probe measurements and the initial attempt in the development of more realistic theoretical models for the prospective improvement of our predictive capability
An experimental and theoretical investigation of XPS and NEXAFS of 5-halouracils
No full textThe C, N and O 1s excitation and ionization processes of 5X-uracil (X = F, Cl, Br, and I) were investigated using near edge X-ray absorption fine structure (NEXAFS) and X-ray photoemission (XPS) spectroscopies. This study aims at the fine assessment of the effects of the functionalization of uracil molecules by halogen atoms having different electronegativity and bound to the same molecular site. Two DFT-based approaches, which rely on different paradigms, have been used to simulate the experimental spectra and to assign the corresponding features. The analysis of the screening of the core holes of the different atoms via electronic charge density plots has turned out to be a useful tool to illustrate the competition between the partially aromatic and partially conjugate properties of this class of molecules. © 2018 the Owner Societies
Insights into 2- and 4(5)-Nitroimidazole Decomposition into Relevant Ions and Molecules Induced by VUV Ionization
No full textNitromidazoles
are relevant compounds of multidisciplinary interest,
and knowledge of their physical–chemical parameters as well
as their decomposition under photon irradiation is needed. Here we
report an experimental and theoretical study of the mechanisms of
VUV photofragmentation of 2- and 4(5)-nitromidazoles, compounds used
as radiosensitizers in conjunction with radiotherapy as well as high-energy
density materials. Photoelectron–photoion coincidence experiments,
measurements of the appearance energies of the most important ionic
fragments, density functional theory, and single-point coupled cluster
calculations have been used to provide an overall insight into the
energetics and structure of the different ionic/neutral products of
the fragmentation processes. The results show that these compounds
can be an efficient source of relevant CO, HCN, NO, and NO2 molecules and produce ions of particular astrophysical interest,
like the isomers of azirinyl cation (m/z 40), predicted to exist in the interstellar medium, and protonated
hydrogen cyanide (m/z 28)
Formation of H3O+ and OH by CO2 and N2O trace gases in the atmospheric environment
No full textThe impact of cosmic rays’ energetic subatomic particles on climate and global warming is still controversial and under debate. Cosmic rays produce ions that can trigger fast reactions affecting chemical networks in the troposphere and stratosphere especially when a large amount of relevant trace gases such as carbon dioxide, methane, sulfur dioxide and water are injected by volcanic eruptions. This work focuses on synchrotron experiments and an ab initio theoretical study of the ion chemistry of carbon dioxide and nitrous oxide radical cations reacting with water. These molecules catalyze a fast exothermic formation of hydronium ions H3O+ and the hydroxyl radical OH, the main oxidant in the atmosphere. Moreover, theoretical calculations demonstrate that at the end of the catalytic cycle, CO2 and N2O are produced vibrationally excited and subsequently they quench in the microsecond time scale by collision with the surrounding atmospheric molecules at the pressure and temperature of the upper-troposphere/stratosphere. The chemistry involved in these reactions has a strong impact on the oxidant capacity of the atmosphere, on the sulfate aerosol production, on the cloud formation and eventually on the chemical networks controlling climate and global warming models
Figure 15 in A comparative atlas of selected skeletal elements of European urodeles (Amphibia: Urodela) for palaeontological investigations
No full textFigure 15. Precaudal vertebrae of Ichthyosaura (A, B) and Lissotriton (C, D), as an example of the intrageneric variation of the posterodorsal area of the neural arch. Notice that in A and C, the posterodorsal area is vertical and followed by the forked neural crest, whereas in B and D the posterodorsal area is roof-shaped, and the neural crest terminates in the middle of the incisura dorsalis. In contrast, the medial edges of the prezygapophyses (dashed lines in A, C) are a less variable character (divergent in the case of Ichthyosaura and parallel in Lissotriton; see diagnoses section). Scale bars: 1 mm.Published as part of Macaluso, Loredana, Wencker, Lukardis C M, Castrovilli, Maria, Carnevale, Giorgio & Delfino, Massimo, 2023, A comparative atlas of selected skeletal elements of European urodeles (Amphibia: Urodela) for palaeontological investigations, pp. 569-619 in Zoological Journal of the Linnean Society 197 (3) on page 615, DOI: 10.1093/zoolinnean/zlac063, http://zenodo.org/record/769095
Figure 8 in A comparative atlas of selected skeletal elements of European urodeles (Amphibia: Urodela) for palaeontological investigations
No full textFigure 8. Atlantes of European urodeles. A, Lissotriton vulgaris (MDHC 135). B, Lissotriton vulgaris (MDHC 133). C, Ommatotriton vittatus (MNCN 13193), with right postzygapophyses missing. D, Pleurodeles waltl (MDHC 253). E, Triturus carnifex (MDHC 38). From left to right: anterior, dorsal, lateral (right lateral for A, D; left lateral for B–C, E), posterior and ventral views. Scale bars: 1 mm.Published as part of Macaluso, Loredana, Wencker, Lukardis C M, Castrovilli, Maria, Carnevale, Giorgio & Delfino, Massimo, 2023, A comparative atlas of selected skeletal elements of European urodeles (Amphibia: Urodela) for palaeontological investigations, pp. 569-619 in Zoological Journal of the Linnean Society 197 (3) on page 579, DOI: 10.1093/zoolinnean/zlac063, http://zenodo.org/record/769095
Effetto dell’età di svezzamento sull’evoluzione del peso vivo e dell’ingestione di alimento solido nel coniglio
No full textDr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
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