199 research outputs found
8-(2-Methoxyphenyl)-6-methyl-2-(1-methyl-1H-benzo[d]imidazol-2-yl)quinoline
For very first time, we report the synthesis of 8-(2-methoxyphenyl)-6-methyl-2-(1-methyl1H-benzo[d]imidazol-2-yl)quinoline 1. This was achieved in several steps, including usage of the
Suzuki reaction for functionalization of 2-(1H-benzo[d]imidazol-2-yl)quinoline moiety. The new
compound exhibits blue fluorescence. Its structure was confirmed with 1D and 2D NMR spectroscopy,
IR spectroscopy, high-resolution mass spectrometry and X-ray analysis
Molecular Design of Luminescent Complexes of Eu(III): What Can We Learn from the Ligands
The luminescent metal-organic complexes of rare earth metals are advanced materials
with wide application potential in chemistry, biology, and medicine. The luminescence of these
materials is due to a rare photophysical phenomenon called antenna effect, in which the excited
ligand transmits its energy to the emitting levels of the metal. However, despite the attractive
photophysical properties and the intriguing from a fundamental point of view antenna effect, the
theoretical molecular design of new luminescent metal-organic complexes of rare earth metals is
relatively limited. Our computational study aims to contribute in this direction, and we model
the excited state properties of four new phenanthroline-based complexes of Eu(III) using the TDDFT/TDA approach. The general formula of the complexes is EuL2A3
, where L is a phenanthroline
with â2âCH3OâC6H4
, â2âHOâC6H4
, âC6H5 or âOâC6H5 substituent at position 2 and A is Clâ or
NO3
â. The antenna effect in all newly proposed complexes is estimated as viable and is expected to
possess luminescent properties. The relationship between the electronic properties of the isolated
ligands and the luminescent properties of the complexes is explored in detail. Qualitative and
quantitative models are derived to interpret the ligand-to-complex relation, and the results are
benchmarked with respect to available experimental data. Based on the derived model and common
molecular design criteria for efficient antenna ligands, we choose phenanthroline with âOâC6H5
substituent to perform complexation with Eu(III) in the presence of NO3ÂŻ. Experimental results
for the newly synthesized Eu(III) complex are reported with a luminescent quantum yield of about
24% in acetonitrile. The study demonstrates the potential of low-cost computational models for
discovering metal-organic luminescent materials
Luminescent Complexes of Europium (III) with 2-(Phenylethynyl)-1,10-phenanthroline: The Role of the Counterions
New antenna ligand, 2-(phenylethynyl)-1,10-phenanthroline (PEP), and its luminescent Eu
(III) complexes, Eu(PEP)2Cl3 and Eu(PEP)2
(NO3
)3
, are synthesized and characterized. The synthetic
procedure applied is based on reacting of europium salts with ligand in hot acetonitrile solutions in
molar ratio 1 to 2. The structure of the complexes is refined by X-ray diffraction based on the single
crystals obtained. The compounds [Eu(PEP)2Cl3
]·2CH3CN and [Eu(PEP)2
(NO3
)3
]·2CH3CN crystal ize in monoclinic space group P21/n and P21/c, respectively, with two acetonitrile solvent molecules.
Intra- and inter-ligand Ï-Ï stacking interactions are present in solid stat and are realized between
the phenanthroline moieties, as well as between the substituents and the phenanthroline units. The
optical properties of the complexes are investigated in solid state, acetonitrile and dichloromethane
solution. Both compounds exhibit bright red luminescence caused by the organic ligand acting as
antenna for sensitization of Eu (III) emission. The newly designed complexes differ in counter ions
in the inner coordination sphere, which allows exploring their influence on the stability, molecular
and supramolecular structure, fluorescent properties and symmetry of the Eu (III) ion. In addition,
molecular simulations are performed in order to explain the observed experimental behavior of the
complexes. The discovered structure-properties relationships give insight on the role of the counter
ions in the molecular design of new Eu (III) based luminescent materials
EVALUATION OF THE APICAL SEAL AFTER POST SPACE PREPARATION: IN VITRO STUDY
Introduction: Large crown destruction often leads to restoring endodontically treated teeth using post and core. As a result of post space preparation, the integrity of the apical seal can be affected, thus increasing the chances of microleakage occurring.
Aim: The goal of the study is to observe and evaluate the quality of the apical seal after post space preparation.
Materials and Methods: 27 extracted single-rooted teeth were used. The coronal part was removed, and the root length was standardized to 15mm. The canals were prepared with Revo-S rotary system, irrigated with 5ml 5.25% sodium hypochlorite, saline, and 2ml 40% citric acid. The canals were filled with Adseal and gutta-percha using cold lateral condensation technique. The teeth were divided into two groups depending on post space preparation speed and one control group: first group (n=9) - 2800 rpm; second group (n=10) - 4700 rpm; control group (n=8) â with no preparation. Nail varnish was applied on the external root surface of the teeth except for the apical 2mm, afterwards, the teeth inserted in 2% methylene blue for 24 hours and then washed under running water for the same time. The teeth were cut longitudinally in a buccal-lingual direction so that the level of dye penetration between the root canal wall and the filling material could be visualized. The measurement was done in mm.
Results: The highest average value of apical penetration was observed in the second group (4700 rpm) - 1.10 mm. The difference of the apical penetration between group 2 (1.10 mm) and control group (0.25mm) is significant, while the average value of Group 1 (2800 rpm) does not differ statistically from the other two groups.
Concussion: Post space preparation combined with the higher speed of the drill can increase the risk of damage the apical seal
The Penn Effect and Transition: The New EU Member States in International Perspective
Recent panel studies have found relatively high point estimates for the elasticity of ag-gregate price measures with respect to productivity in (former) transition economies, while other studies report price-productivity elasticity estimates to depend positively on average productivity in the sample. We aim to reconcile both results by putting com-parative price developments of transition economies in an international perspective. We argue that estimating simple price-productivity relationships without the inclusion of other real factors connected to reform effort might severely bias estimates for CEEC economies. Our results imply that, when controlling for reform effort and therefore avoiding this endogeneity problem, the price-productivity-elasticity for CEEC econo-mies was not different from that of non-transition economies during the first 15 years of transition
Autistic Adult Services Availability, Preferences, and User Experiences : Results From the Autism Spectrum Disorder in the European Union Survey
There is very little knowledge regarding autistic adult services, practices, and delivery. The study objective was to improve understanding of current services and practices for autistic adults and opportunities for improvement as part of the Autism Spectrum Disorder in the European Union (ASDEU) project. Separate survey versions were created for autistic adults, carers of autistic adults, and professionals in adult services. 2,009 persons responded to the survey and 1,085 (54%) of them completed at least one of the services sections: 469 autistic adults (65% female; 55% 50% responded "don't know"). Five of seven residential services features recommended for autistic adults were experienced byPeer reviewe
Real-World Experiences in Autistic Adult Diagnostic Services and Post-diagnostic Support and Alignment with Services Guidelines: Results from the ASDEU Study
Research providing an evidence-base for autistic adult services is sparse. The Autism Spectrum Disorders in the European Union (ASDEU) network implemented an on-line survey to determine gaps in autistic adult diagnostic evaluation and post-diagnostic support services. More than 55% in all groups experienced most of the recommended features for diagnostic evaluation for autistic adults. In contrast, < 2% of adults or carers, and < 21% of professionals experienced each of the recommended features for post-diagnostic support. In contrast to 61% of professionals, only about 30% of autistic adults and carers had knowledge of good local services models for autism diagnosis in adulthood. There are major differences between good practice guidelines for diagnostic and post-diagnostic care for autistic adults, and what is actually experienced by services users and professionals
Autistic Adult Health and Professional Perceptions of It: Evidence From the ASDEU Project
The Autism Spectrum Disorders in the European Union (ASDEU) survey investigated the knowledge and health service experiences of users and providers to generate new hypotheses and scientific investigations that would contribute to improvement in health care for autistic adults. An online survey designed for autistic adults, carers of autistic adults, and professionals in adult services was translated into 11 languages and distributed electronically by organizations and in-country adult service facilities in 2017; 522 autistic adults, 442 carers, and 113 professionals provided answers to the health questions. Professionals, the majority in non-medical services, appeared to be poorly informed about whether certain co-occurring conditions were more frequent in autistic adults than typical adults-especially some medical conditions, suicide attempts, accidents, and pain. A minority of autistic adults reported preventive health behaviors such as routine health check-ups. The majority of users and providers expressed the desire to make health care services more user-friendly for autistic adults. Among the three groups, <20% of responders knew an organization or clinician which has developed a way to monitor health, and prevent poor health, that works well for adults on the autism spectrum. The results point to means for better management of co-occurring conditions associated with autism in adulthood in order to reduce hospital admissions and potential areas of improvement in health and social services for autistic adults. Specifically, efforts should be focused on (1) professionals' education on risks for co-occurring conditions in autistic adults; (2) promoting preventive health behaviors; (3) making services user-friendly for autistic adults and their families; and (4) encouraging knowledge of good local services
Intervention Services for Autistic Adults: An ASDEU Study of Autistic Adults, Carers, and Professionals' Experiences
The Autism Spectrum Disorders in the European Union (ASDEU) survey investigated local services' use experiences of autistic adults, carers and professionals with interventions for autistic adults. The majority of the 697 participants experienced recommended considerations prior to deciding on intervention and during the intervention plan and implementation. Psychosocial interventions were the most commonly experienced interventions, while pharmacological interventions NOT recommended for core autistic symptoms were reported by fairly large proportions of participants. Family interventions were experienced slightly more commonly by carers than adults or professionals. Less than the 26% of autistic adult responders who had experienced challenging behaviors reported receiving an intervention to change them. These results provide insights for improving gaps in service provision of interventions among autistic adults
Human impact erodes chimpanzee behavioral diversity
Chimpanzees possess a large number of behavioral and cultural traits among nonhuman species. The âdisturbance hypothesisâ predicts that human impact depletes resources and disrupts social learning processes necessary for behavioral and cultural transmission. We used a dataset of 144 chimpanzee communities, with information on 31 behaviors, to show that chimpanzees inhabiting areas with high human impact have a mean probability of occurrence reduced by 88%, across all behaviors, compared to low-impact areas. This behavioral diversity loss was evident irrespective of the grouping or categorization of behaviors. Therefore, human impact may not only be associated with the loss of populations and genetic diversity, but also affects how animals behave. Our results support the view that âculturally significant unitsâ should be integrated into wildlife conservation
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