285 research outputs found
Maintaining a Virtual Professional Community Through Positive Word of Mouth
To better understand the sustainability of a virtual professional community, the authors develop and test a research model of user intention to recommend the community to others. Specifically, intention to spread positive word of mouth is proposed to be determined by satisfaction, commitment, and group norm, with satisfaction and group norm positively impacting commitment. Using data obtained from users of a virtual professional community (an educational portal), the results supported nearly all hypothesized relationships. Only the relationship between satisfaction and commitment was not found to be significant. The authors conclude with a discussion of the findings and implications for both theory and practice
Nickel(II) complexes of novel thiosemicarbazone compounds: Synthesis, characterization, molecular modeling and in vitro antimicrobial activity
A series of novel thiosemicarbazone compounds, HL1, 2-(1-(2-phenyl-hydrazono)-propan-2-ylidene)hydrazine-carbothioamide (TPHP), HL2, N-methyl-2-(1-(2-phenyl-hydrazono)-propan-2-ylidene)hydrazinecarbothioamide (MTPHP) and, HL3, N-phenyl-2-(1-(2-phenyl-hydrazono)-propan-2-ylidene)hydrazinecarbothioamide (PTPHP) and their Ni(II) complexes have been synthesized and characterized using elemental analysis, magnetic susceptibility, molar conductance and spectral measurements. IR spectra indicate that the free ligands exist in the thione form rather than thiol form in the solid state. In all the studied complexes, all ligands behave as a tridenate anion with coordination involving the two azomethine nitrogens and the thiolate sulfur after deprotonation. The magnetic and spectral data indicates a square planar geometry for Ni(II) complexes. The structures of the free thiosemicarbazone ligands and their Ni(II) complexes have been modelled using parameterized PM3 semiempirical method. The free ligands and their Ni(II) chelates have been screened for their antimicrobial activities
Synthese und Hofmann-Abbau des 1-(Diphenyl-hydroxymethyl)-2,2-dimethyl-6,7-dimethoxy-1,2,3,4-tetrahydroisochinolinium-Ions
Summary. The synthesis of the N-quaternary aminoalcohol 6 is described. Analogous to the
aminoalcohols 1 and 2, 6 on treatment w i t h alkali undergoes fission of the substituent at C(l) as a
carbonyl compound, with formation of a N, N-dimethyl-l,2,3,4-tetrahydroisoquinolinium ion,
which is further degraded to the corresponding o-vinyl-benzylamine {Scheme 7). - As a by-product
of a Bischler-Napieralski ring closure, we observed chlorination of an aromatic ring (yielding 19)
Synthese undHOFMANN-Abbau des 1-(Diphenyl-hydroxymethyl)-2,2-dimethyl-6,7-dimethoxy-1,2,3,4-tetrahydroisochinolinium-Ions
Sterically demanding oxidative amidation of alpha-substituted malononitriles with amines using O2
An efficient amidation method between readily available 1,1-dicyanoalkanes and chiral or non-chiral amines was realized simply with molecular oxygen and a carbonate base. This oxidative protocol can be applied to both sterically and electronically challenging substrates in a highly chemoselective, practical, and rapid manner. The use of cyclopropyl and thioether substrates support the radical formation of alpha-peroxy malononitrile species, which can cyclize to dioxiranes that can monooxygenate malononitrile alpha-carbanions to afford activated acyl cyanides capable of reacting with amine nucleophiles
Identification and analysis of a conserved immunoglobulin E-binding epitope in soybean G1a and G2a and peanut Ara h 3 glycinins
Work Engagement among Rescue Workers: Psychometric Properties of the Portuguese UWES
Rescue workers have a stressful and risky occupation where being engaged is crucial to face physical and emotional risks in order to help other persons. This study aims to estimate work engagement levels of rescue workers (namely comparing nurses, firefighters, and police officers) and to assess the validity evidence related to the internal structure of the Portuguese versions of the UWES-17 and UWES-9, namely, dimensionality, measurement invariance between occupational groups, and reliability of the scores. To evaluate the dimensionality, we compared the fit of the three-factor model with the fit of a second-order model. A Portuguese version of the instrument was applied to a convenience sample of 3,887 rescue workers (50% nurses, 39% firefighters, and 11% police officers). Work engagement levels were moderate to high, with firefighters being the highest and nurses being the lowest engaged. Psychometric properties were evaluated in the three-factor original structure revealing acceptable fit to the data in the UWES-17, although the UWES-9 had better psychometric properties. Given the observed statistically significant correlations between the three original factors, we proposed a 2nd hierarchal structure that we named work engagement. The UWES-9 first-order model obtained full uniqueness measurement invariance, and the second-order model obtained partial (metric) second-order invariance
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