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The sensing mechanism of 2-hydroxy-1-naphthaldehyde-(4-pyridinecarboxylic)- hydrazone for [Al.sup.3+] is investigated based on the excited-state intramolecular proton transfer (ESIPT) and photo- induced electron transfer (PET) processes. Absorption and fluorescence spectra are calculated, which are consistent with experimental results. By analyzing the major bond parameters, infrared vibrational spectra as well as frontier molecular orbitals, it can be concluded that the hydrogen bond is enhanced in the first singlet excited state ([S.sub.1]), which can also be visualized by the reduced density gradient function. Potential energy curves are also scanned, which can elucidate that the ESIPT process is more likely to occur in the [S.sub.1] state. Changes in molecular configuration and intensity of fluorescence emission confirmed that the ESIPT and PET processes are forbidden in the presence of [Al.sup.3+]. Key words: ESIPT, hydrogen bond, [Al.sup.3+] sensing, reduced density gradient, potential energy curve. Nous examinons le mecanisme de detection de [Al.sup.3+], du compose 2-hydroxy- naphthaldehyde-(4- pyridicarboxyclique)hydrazone, sur la base du transfert intramoleculaire de proton de l'etat excite (TIPEE) et des processus de transfert electronique induit par photon (TEP). Nos calculs des spectres d'absorption et de fluorescence s'averent coherents avec les valeurs experimentales. En analysant les parametres de liaisons majeures, les spectres vibrationnels infrarouges, ainsi que les orbitales moleculaires frontieres, nous pouvons conclure que la liaison hydrogene est renforcee dans le premier etat excite singlet ([S.sub.1]), ce qui peut aussi etre visualise par la fonction du gradient de densite reduite. Nous balayons egalement les courbes d'energie potentielle, ce qui peut eclaircir le fait que le processus TIPEE a plus de probabilite de se produire dans l'etat [S.sub.1]. Les changements dans la configuration moleculaire et l'intensite de remission de fluorescence confirment que les mecanismes TIPEE et TEP sont interdits en presence de [Al.sup.3+]. [Traduit par la Redaction] Mots-cles: TIPE, liaison hydrogene, courbe d'energie potentielle, detection de [Al.sup.3+], gradient de densite reduite., 1. Introduction Intra- and intermolecular hydrogen bonds are crucial in the study of photochemistry, photophysics, and photobiology [1-4]. Hydrogen bond dynamics have been the subject of a lot of studies [...]

OBJECTIVE. This study sought to examine the usefulness of non-high-density lipoprotein cholesterol levels in predicting future dyslipidemia and other cardiovascular risk in adulthood. METHODS. The study sample consisted of a longitudinal cohort of subjects (n = 1163; 30.1% black and 55.4% female) who participated in the Bogalusa Heart Study both as children at 5 to 14 years of age and as adults 27 years later. RESULTS. The childhood level of non-high-density lipoprotein cholesterol, like low-density lipoprotein cholesterol, was the best predictor of the adulthood level; the next best predictor for both variables was the change in BMI from childhood to adulthood. Furthermore, those in the age-, race-, and gender-specific top quartile, compared with those in the bottom quartile, of non-high-density lipoprotein cholesterol and low-density lipoprotein cholesterol levels in childhood were 4.5 and 3.5 times more likely, respectively, to develop adult dyslipidemia, independent of baseline BMI and BMI change after 27 years. Although, at equivalent cutoff points, childhood high-risk versus acceptable-risk status for both lipid measures was associated significantly with increased prevalence of obesity and adverse levels of low-density lipoprotein cholesterol and triglycerides in adulthood, only childhood non-high-density lipoprotein cholesterol high-risk status was associated with increased prevalence of low high-density lipoprotein cholesterol levels, hyperinsulinemia, and hyperglycemia (marginal). CONCLUSIONS. Adverse levels of non-high-density lipoprotein cholesterol versus low-density lipoprotein cholesterol in childhood not only equally persist over time and better predict adult dyslipidemia but also are related to nonlipid cardiovascular risk factors in adulthood. www.pediatrics.org/cgi/doi/10.15421 peals.2005-1856 doi:10.15421peds.2005-1856 Key Words non-high-density lipoprotein cholesterol, low-density liDoorotein cholesterol, childhood, adulthood, tracking, coronary artery disease risk Abbreviations CAD--coronary artery disease HDL--high-density lipoprotein LDL--low-density lipoprotein, ADVERSE LEVELS OF serum lipoprotein cholesterols have long been recognized as an important risk factor for coronary artery disease (CAD) among adults. (1) Furthermore, adverse levels among youths are associated [...]