Portable X-ray fluorescence of zinc and selenium with nail clippings – visit 3 of the Mother and Infant Nutrition Investigation (MINI)
Notice bibliographique
Résumé
INTRODUCTION: Recent advances in portable X-ray fluorescence (XRF) have opened up the possibility of a rapid and cost-effective method for measuring elemental content in nail clippings. Two elements of particular interest for intake assessment through nail clipping measurement are zinc and selenium. The New Zealand-based Mother and Infant Nutrition Investigation (MINI) provides an ideal testing ground for the application of portable XRF in the measurement of zinc and selenium. Two aspects requiring further study with portable XRF are the optimal time of measurement and the optimal approach to energy spectrum analysis. METHODS: A subset of nail clippings from 20 mother-infant pairings were initially selected for analysis over three separate MINI study visits. This paper considers measurements from visit 3 (12 months postpartum). For portable XRF, a mono-energetic X-ray beam was used to excite characteristic X-rays from zinc and selenium. Individual XRF measurements were made for 60 s (real time). In each case, analysis of the elemental signal was performed in four different ways: (1) automated system output concentration; (2) element signal to total signal ratio; (3) element signal to Compton scatter signal; (4) element signal to coherent scatter signal. XRF results were compared against zinc and selenium concentrations obtained from a "gold standard" method of inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: ICP-MS results from the visit 3 nail clippings determined a mean zinc concentration of 104 µg/g and a mean selenium concentration of 0.606 µg/g. Analysis of XRF energy spectra from 60 s measurements showed that zinc was clearly detected in all cases. The selenium signal was more challenging, but was also detected from all spectra. For both zinc and selenium, correlations between XRF results and ICP-MS concentrations were highly significant (p < 0.01) in all cases, with the zinc results more strongly correlated than selenium. Of the four approaches to XRF signal analysis, the three approaches involving an external software package provided superior results relative to the automated system output. Correlations of XRF results with ICP-MS concentrations were similar between these three approaches. CONCLUSION: ICP-MS concentrations for both zinc and selenium were found to be lower from visit 3 relative to results from visit 1 and visit 2. This may indicate overall dietary changes postpartum. Correlations of XRF results with ICP-MS concentrations suggest that a relatively short 60 s measurement time is adequate for a reliable zinc assessment, but not for selenium. Although correlations of XRF results with ICP-MS concentrations were similar between three different methods of spectra analysis, practical considerations may favor use of the element signal to total signal approach.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,001 |
| Bibliométrie | 0,001 | 0,000 |
| Études des sciences et des technologies | 0,001 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,001 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,010 | 0,002 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».