Search results for "complex"

The migration–tourism nexus in the EU28

2020

This study explores the nexus between tourism and migration on an intra-European scale over the period 2000–2015. Complex-network analysis and gravity models were the investigation methods preferred. For each year under study, we built two country-to-country networks to map and reveal the connections between states as shaped by migration stocks and tourism flows, respectively. Then, the main determinants of the correlation patterns between the two networks were investigated by several econometric analysis. Results point to a quite similar topological structure for the tourism and migration networks as well as to a significant and reciprocal direct influence between tourism and migration mo…

Etude de certaines familles de variétés algébriques munies d'une action de groupe algébrique

2021

REMOTELY PILOTED AIRCRAFT SYSTEMS (RPAS) APPLICATION FOR STRUCTURE DESCRIPTION OF MEDITERRANEAN VERMETID REEFS

2016

Vermetid gastropods are coastal habitat engineers which build biogenic platforms typical of intertidal rocky shores of central and south -east of the Mediterranean. These bioconstructions create a secondary habitat which increases resource availability and space for organisms, locally transforming the environment and modifying coastal geomorphology. Biological characteristics and physical structure of these bioconstructions are commonly studied by field-based sampling. Nevertheless, a lot of time is required to collect data over large areas of reef, field conditions can impair data collection and direct reef image interpretation may be a challenge due to their intertidal position. In this s…

Managing complexity in global IT projects

2017

Projektien hallintaan kuuluu paljon erilaisia osa-alueita, joita projektipäällikön ja korkeamman tason henkilöstön tulee ottaa huomioon ennen projektin alkua ja sen aikana. Projektin kompleksisuus nousee kuitenkin erittäin korkealle ta-solle, kun kyseessä on kansainvälinen IT-projekti. Tämän kaltaisissa projek-teissa on useita osa-alueita, jotka voivat vaikuttaa kriittisesti niiden onnistumi-seen. Tämä tutkimus keskittyy havainnoimaan, mistä asioista kompleksisuus koostuu globaalien IT-projektien tapauksessa, miten se linkittyy kompleksi-suusteoriaan ja miten tätä kompleksisuutta kyetään hallitsemaan. Tekotapana tässä tutkimuksessa on kirjallisuuskatsaus. Kirjallisuus on kerätty kirjastoist…

Combination vaccines containing DTPa–Hib: impact of IPV and coadministration of CRM197 conjugates

2008

Vaccination with diphtheria-tetanus-acellular pertussis (DTPa)-Haemophilus influenzae type b (Hib) combinations generally elicits anti-polyribosyl-ribitol-phosphate (PRP) antibody concentrations of more than 0.15 microg/ml, a criterion that is linked to the protection of infants against Hib disease. In the UK, vaccination with DTPa3-Hib elicited atypically low anti-PRP antibody levels and was associated with breakthrough Hib cases. While the absence of a toddler booster is considered to be a key factor explaining the lowered control of Hib disease, we propose that the coadministration of serogroup C Neisseria meningitidis conjugate vaccine (MenC)-CRM197, which coincided with the introductio…

Standards for the diagnosis and management of complex regional pain syndrome: Results of a European Pain Federation task force.

2019

Background: Complex regional pain syndrome is a painful and disabling post-traumatic primary pain disorder. Acute and chronic complex regional pain syndrome (CRPS) are major clinical challenges. In Europe, progress is hampered by significant heterogeneity in clinical practice. We sought to establish standards for the diagnosis and management of CRPS. Methods: The European Pain Federation established a pan-European task force of experts in CRPS who followed a four-stage consensus challenge process to produce mandatory quality standards worded as grammatically imperative (must-do) statements. Results: We developed 17 standards in 8 areas of care. There are 2 standards in diagnosis, 1 in multi…

Approach to equilibrium of a quarkonium in a quark-gluon plasma

2018

We derive equations of motion for the reduced density matrix of a heavy quarkonium in contact with a quark-gluon plasma in thermal equilibrium. These equations allow in particular a proper treatment of the regime when the temperature of the plasma is comparable to the binding energy of the quarkonium. These equations are used to study how the quarkonium approaches equilibrium with the plasma, and we discuss the corresponding entropy increase, or free energy decrease, depending on the temperature regime. The effect of collisions can be accounted for by the generalization of the imaginary potential introduced in previous studies, and from which collision rates are derived. An important outcom…

Interplay of acidity and ionic liquid structure on the outcome of a heterocyclic rearrangement reaction

2021

The study of suitable probe reactions is a powerful tool to investigate the properties of nonconventional solvents such ionic liquids (ILs). In particular, we studied the acid-catalyzed mononuclear rearrangement of heterocycles (MHR) of the Z-phenylhydrazone of 5-amino-3-benzoyl-1,2,4-oxadiazole into the relevant 1,2,3-triazole, in solution of ILs by means of kinetic measurements. We chose as solvents six ILs differing both in the cation and anion, in the presence of five carboxylic and sulfonic acids as catalysts. For a useful comparison, the reaction was also performed in 1,4-dioxane and methanol. In general, the reaction occurs faster in ILs, compared to conventional solvents, according …

A three-coordinate iron–silylene complex stabilized by ligand–ligand dispersion forces

2016

The structural and bonding properties of a three-coordinate N-heterocyclic silyene (NHSi) complex of the iron(II) amide [Fe{N(SiMe3)2}2] are reported. Computational studies reveal that dispersion forces between the amido SiMe3 substituents and the isopropyl substituents on the NHSi ligand significantly enhance the stability of the complex, along with Fe-to-Si π-backbonding. peerReviewed

Simultaneous Endo- and Exo-Complex Formation of Pyridine[4]arene Dimer with Neutral and Anionic Guests

2017

The formation of complexes between hexafluorophosphate (PF6−) and tetraisobutyloctahydroxypyridine[4]arene has been thoroughly studied in the gas phase (ESI‐QTOF‐MS, IM‐MS, DFT calculations), in the solid state (X‐ray crystallography), and in chloroform solution (1H, 19F, and DOSY NMR spectroscopy). In all states of matter, simultaneous endo complexation of solvent molecules and exo complexation of a PF6− anion within a pyridine[4]arene dimer was observed. While similar ternary complexes are often observed in the solid state, this is a unique example of such behavior in the gas phase. peerReviewed