Search results for "Negativity"

showing 10 items of 301 documents

Modeling the magnetic properties of lanthanide complexes: relationship of the REC parameters with Pauling electronegativity and coordination number

2015

In a previous study, we introduced the Radial Effective Charge (REC) model to study the magnetic properties of lanthanide single ion magnets. Now, we perform an empirical determination of the effective charges (Zi) and radial displacements (Dr) of this model using spectroscopic data. This systematic study allows us to relate Dr and Zi with chemical factors such as the coordination number and the electronegativities of the metal and the donor atoms. This strategy is being used to drastically reduce the number of free parameters in the modeling of the magnetic and spectroscopic properties of f-element complexes. SPINMOL FP7-ERC-247384 ERC-CoG-647301 DECRESIM MAT2011-22785 MAT2014-56143-R CTQ2…

LanthanideSingle ionChemistryCoordination numberUNESCO::QUÍMICA02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesMolecular physics:QUÍMICA [UNESCO]Effective nuclear charge0104 chemical sciencesInorganic ChemistryElectronegativityMetalComputational chemistryvisual_artMagnetvisual_art.visual_art_medium0210 nano-technologyFree parameter
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1H and13C n.m.r. spectra of dichloro(trans-2-chlorovinyl)arsine

1977

Proton and carbon magnetic resonance spectra of Lewisite or dichloro(trans-2-chlorovinyl)arsine have been measured and the results are compared with the n.m.r. spectral parameters of other trans-1,2-substituted ethylenes. The coupling constants can be rationalized by substituent electronegativity. The chemical shifts show an unusually large paramagnetic effect from the AsCl2 group.

LewisiteProtonChemical shiftSubstituentchemistry.chemical_elementGeneral ChemistryPhotochemistrySpectral lineElectronegativitychemistry.chemical_compoundArsinechemistryPhysical chemistryGeneral Materials ScienceCarbonOrganic Magnetic Resonance
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Heterocyclic systems containing tin(IV)—XIII [1]. Possible ceasing or inversion of the structuraltrans influence during the course of a bimolecular n…

1997

Abstract In the series of the heterocycles X[(CH2)3]2SnR2 (16 newly synthesized compounds and two taken from the literature) and in the germanium analog BuiN[(CH2)3]2GeCl2, the donor group X (= NMe, NBz, NBui, NPri, O, S) intramolecularly attacks the Lewis acidic atoms Sn or Ge. Eight structure determinations (and, in addition, 2 taken from the literature) are compared. The nucleophilic attack at Sn is stronger for the ligands R2 =Cl2 than for the more electronegative R2 = (OSiPh3)2. Overall the familiartrans influence holds: simultaneous approach of X and weakening of the ligand R (trans). In three cases of subtly graded donor strength a slight inversion or ceasing is observed: shorter dis…

LigandChemistryChemical shiftchemistry.chemical_elementGermaniumInorganic ChemistryElectronegativityCrystallographyNucleophileAtomic orbitalComputational chemistryMaterials ChemistryTetrahedronPhysical and Theoretical ChemistryTinPolyhedron
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Therapeutic management and evolution of chronic hepatitis B: does HIV still have an impact? The EPIB 2012 study

2015

EA Pôle MERS Hors CT hors EJ; International audience; Background & Aims: To compare the management of chronic hepatitis B (CHB) and its evolution over time in currently followed HIV-positive and HIV-negative patients. Methods: A total of 709 consecutive patients with past or present positive HBs antigenemia seen in October 2012 in 19 French participating centres were included. The data were retrospectively collected from the first visit onwards through standardized questionnaires. Results: Chronic hepatitis B was less often assessed in the 299 HIV-positive patients, who were older, more likely to be male, excessive alcohol drinkers and HBe antigen-, HCV- and HDV-positive. They were also fol…

Liver CirrhosisMale[SDE] Environmental SciencesCirrhosis[SDV]Life Sciences [q-bio]HIV InfectionsComorbidityCohort Studies0302 clinical medicineReference ValuesHIV SeropositivityHBV[SDV.BV] Life Sciences [q-bio]/Vegetal Biology030212 general & internal medicineHIV SeronegativityLiver NeoplasmsLamivudinevirus diseasesEntecavirhepatocellular carcinomaMiddle Aged3. Good health[SDV] Life Sciences [q-bio]Treatment OutcomeLamivudineHepatocellular carcinoma[SDE]Environmental SciencesDisease ProgressionFemale030211 gastroenterology & hepatologyFranceCohort studymedicine.drugAdultmedicine.medical_specialtyGuanineAntiviral AgentsRisk AssessmentStatistics Nonparametric03 medical and health sciencesHepatitis B ChronicHIV SeronegativityInternal medicinemedicineHumans[SDV.BV]Life Sciences [q-bio]/Vegetal BiologySurvival analysisRetrospective StudiesHepatitis B Surface AntigensHepatologybusiness.industrycirrhosisHIVmedicine.diseaseSurvival AnalysisComorbiditytenofovirLogistic ModelsMultivariate AnalysisImmunologybusinessentecavir
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Gendered pathways to romantic attachment in emerging adults: The role of body image and parental support

2015

This study analyses the impact of body image and perceived parental behaviour (support and negativity) as factors that contribute to romantic attachment in emerging adulthood. In a 11-year longitudinal study on 144 females and 114 males, we assessed body image, body mass index, and perceived father's and mother's support and negativity during adolescence (at ages 14 and 17) and in emerging adulthood (age 21). At the age of 25, romantic attachment was assessed. Results of path analyses revealed that females' positive body image was consistently linked with greater parental support over time and contributed to low avoidance in romance at the age of 25, whereas perceived negativity with father…

Longitudinal studyPositive body imageParental supportSocial PsychologyDevelopmental and Educational PsychologyNegativity effectYoung adultPsychologyRomanceBody mass indexDevelopmental psychologyEuropean Journal of Developmental Psychology
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Infant brain responses associated with reading-related skills before school and at school age

2011

Summary Introduction In Jyvaskyla Longitudinal Study of Dyslexia, we have investigated neurocognitive processes related to phonology and other risk factors of later reading problems. Here we review studies in which we have investigated whether dyslexic children with familial risk background would show atypical auditory/speech processing at birth, at six months and later before school and at school age as measured by brain event-related potentials (ERPs), and how infant ERPs are related to later pre-reading cognitive skills and literacy outcome. Patients and methods One half of the children came from families with at least one dyslexic parent (the at-risk group), while the other half belonge…

Longitudinal studySpeech perceptionmedia_common.quotation_subjecteducationMismatch negativityta6121behavioral disciplines and activitiesDevelopmental psychologyDyslexiaRisk FactorsPhysiology (medical)Reading (process)medicineHumansCognitive skillLongitudinal StudiesChildEvoked Potentialsta515media_commonDyslexiaAge FactorsInfant NewbornBrainInfantPhonologyGeneral Medicinemedicine.diseaseNeurologyReadingChild PreschoolSpeech PerceptionNeurology (clinical)PsychologyNeurocognitivepsychological phenomena and processesNeurophysiologie clinique-clinical neurophysiology
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Mismatch-like event-related potentials to pitch deviances in the cerebellar interpositus nucleus and the effect of its temporary inactivation in rabb…

2000

MMNcoolingIPmismatch negativitydeviant alone conditionrabbitoddball conditioninterpositus nucleusevent-related potentialsERP
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Evaluation and extraction of mismatch negativity through exploiting temporal, spectral, time-frequency, and spatial features

2010

MMNindependent component analysismismatch negativityelektrofysiologiaElectroencephalographywavelet decompositionEEGEvoked potentialspoikkeavuusnegatiivisuusevent-related potentialsERPherätepotentiaalit
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Auditory duration discrimination in children with reading disorder, attention deficit or both

2009

Tiina Huttunen-Scott tutki väitöskirjassaan kuulonvaraisen keston erottelun ongelmien esiintymistä lapsilla, joilla on vaikeuksia joko lukemisessa, tarkkaavaisuudessa tai molemmissa. Kuullun erottelun ongelmat voivat vaikuttaa puheäänteiden hahmottamiseen ja prosessointiin ja johtaa vaikeuksiin lukemaan oppimisessa.Huttunen-Scott havaitsi kuullun keston erottelun olevan merkitsevästi heikentynyt lapsilla, joilla on lukemisvaikeuksia. Erottelu oli heikentynyt jopa laajemmin lapsilla, joilla on lukemisvaikeuksien ohella myös tarkkaavaisuuden ongelmia. Sen sijaan lapsilla, joilla on vain tarkkaavaisuuden ongelmia, erottelu ei ollut heikentynyt, mikä viittaa siihen, että kuulonvaraisen prosesso…

MMNlukihäiriöfysiologiamismatch negativitykuuleminenkestotarkkaavaisuuskuulo
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Electrophysiological correlates of memory-based visual change detection in humans

2005

MMNvarhainen vastevisuaalisuusherätevastemuutosearly responseevent-related potentialhavainnointimismatch negativityvisualhumanihminenchange detectionERP
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