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1.
Phys Rev Lett ; 131(26): 263201, 2023 Dec 29.
Article de Anglais | MEDLINE | ID: mdl-38215384

RÉSUMÉ

Molecular lattice clocks enable the search for new physics, such as fifth forces or temporal variations of fundamental constants, in a manner complementary to atomic clocks. Blackbody radiation (BBR) is a major contributor to the systematic error budget of conventional atomic clocks and is notoriously difficult to characterize and control. Here, we combine infrared Stark-shift spectroscopy in a molecular lattice clock and modern quantum chemistry methods to characterize the polarizabilities of the Sr_{2} molecule from dc to infrared. Using this description, we determine the static and dynamic blackbody radiation shifts for all possible vibrational clock transitions to the 10^{-16} level. This constitutes an important step toward millihertz-level molecular spectroscopy in Sr_{2} and provides a framework for evaluating BBR shifts in other homonuclear molecules.

2.
Phys Rev Lett ; 125(15): 153001, 2020 Oct 09.
Article de Anglais | MEDLINE | ID: mdl-33095629

RÉSUMÉ

Optical trapping of molecules with long coherence times is crucial for many protocols in quantum information and metrology. However, the factors that limit the lifetimes of the trapped molecules remain elusive and require improved understanding of the underlying molecular structure. Here we show that measurements of vibronic line strengths in weakly and deeply bound ^{88}Sr_{2} molecules, combined with ab initio calculations, allow for unambiguous identification of vibrational quantum numbers. This, in turn, enables the construction of refined excited potential energy curves, informing the selection of magic wavelengths that facilitate long vibrational coherence. We demonstrate Rabi oscillations between far-separated vibrational states that persist for nearly 100 ms.

3.
Eur J Clin Nutr ; 70(10): 1151-1154, 2016 10.
Article de Anglais | MEDLINE | ID: mdl-27245206

RÉSUMÉ

BACKGROUND/OBJECTIVES: Human milk (HM) is the best possible food for all infants, especially for preterm ones, but lactation and breastfeeding are very difficult for mothers of preterm babies and high rates of breastfeeding difficulties have been reported. Our aim was to investigate the efficacy of a galactogogue containing silymarin-phosphatidylserine and galega in increasing milk production during the first month after delivery in a population of mothers of preterm infants. SUBJECTS/METHODS: Mothers of infants with gestational age (GA) between 27+0 and 32+6 weeks were enrolled in this prospective, double-blind, randomized trial and were randomly allocated to receive either the galactogogue containing silymarin-phosphatidylserine and galega, 5 g/day (galactogogue group, GG), or a placebo, 5 g of lactose per day (placebo group, PG) from the 3rd to the 28th day after delivery. RESULTS: Fifty mothers were included in each group. General characteristics of mothers and pregnancies were similar. Milk production was significantly greater in the GG at the 7th day of life and at the 30th day of life. Daily milk production from the 7th to the 30th day of life was 200 (110-380) ml in the GG vs 115 (60-245) ml in the PG (P<0.0001). The total production of milk during the study period was significantly higher in the GG (6523±5298 ml vs 4136±4093 ml; P<0.02). At the end of the study, 45 mothers of the GG were able to reach the target of milk supply of 200 ml/day compared with 25 mothers of the PG (P<0.01). No adverse reactions were noticed in the study groups. CONCLUSIONS: Silymarin-phosphatidylserine and galega increased milk production in mothers of preterm infants without any significant side effects.


Sujet(s)
Allaitement naturel , Galactogogues/usage thérapeutique , Galega , Prématuré , Lactation/effets des médicaments et des substances chimiques , Silymarine/usage thérapeutique , Adulte , Méthode en double aveugle , Femelle , Galactogogues/pharmacologie , Humains , Nouveau-né , Grossesse , Études prospectives , Silymarine/pharmacologie , Résultat thérapeutique
4.
Minerva Pediatr ; 62(3 Suppl 1): 113-5, 2010 Jun.
Article de Italien | MEDLINE | ID: mdl-21090080

RÉSUMÉ

OBJECTIVE: The aim of this study was to asses the validity of the TCB nomogram for the European population for predicting significant hyperbilirubinemia in healthy term and late-preterm newborns. METHODS: This observational study was conducted from February 2009 to December 2009 in the well-baby nurseries of Gemelli hospital of Rome. The predictive ability of the skin bilirubin (TCB) nomogram was prospectively assessed in 926 neonates with gestational age ?35 weeks. TCB was measured with Bilichek and total serum bilirubin (TSB) was contemporary assayed by the standard spectrophotometric method. Every neonate was assess for a single TCB and TSB value. RESULTS: The mean TSB values was 8.2 +/- 3.2 mg/dl, while the mean TCB values was 9.5 +/- 3.6 mg/dl A sensitivity of 100% and a negative predictive value of 100% were obtained with a single bilirubin determination applying the 75 degrees percentile of our nomogram. CONCLUSION: The 75 degrees percentile of the skin bilirubin nomogram for the European population in the first 96 hours of life is able to predict all neonates at risk of severe hyperbilirubinemia. It could facilitate a safe discharge from the hospital and a targeted intervention and follow-up reducing the need for blood samples.


Sujet(s)
Bilirubine/analyse , Hyperbilirubinémie/métabolisme , Nouveau-né/métabolisme , Maladies du prématuré/métabolisme , Monitorage physiologique/méthodes , Nomogrammes , Peau/métabolisme , Bilirubine/sang , Allaitement naturel , Césarienne/statistiques et données numériques , Accouchement (procédure)/statistiques et données numériques , Femelle , Âge gestationnel , Humains , Hyperbilirubinémie/sang , Préparation pour nourrissons , Prématuré , Mâle , Valeur prédictive des tests , Spectrophotométrie , Facteurs temps
5.
Acta Gastroenterol Belg ; 72(3): 296-300, 2009.
Article de Anglais | MEDLINE | ID: mdl-19902861

RÉSUMÉ

AIM: The purpose of this study was to estimate the caloric intake and fat consumption in children with celiac disease (CD) following a gluten-free diet (GFD). PATIENTS AND METHODS: This study enrolled 100 subjects, including 50 children with CD on a gluten-free diet and a control group of 50 healthy children. Statistical analysis to compare groups was performed using one-way ANOVA. RESULTS: A significant increase in fat consumption was observed in children with CD as compared to healthy children. The daily fat intake was 72.5 +/- 37.2 g per 100 g of food in the CD group and 52.9 +/- 35.4 g per 100 g of food in the control group (p < 0.008). A significant difference in fat intake was found between celiac and healthy females (10.21 +/- 3.15 g/100 g in the celiac group vs 7.46 +/- 2.91 g/100 g in the control group), p = 0.004. CONCLUSIONS: This study describes a significantly higher fat consumption in patients with CD on GFD as compared to controls. This increase was more pronounced in females and during the puberal age. Based on these interesting preliminary results we estimate that further investigations are necessary, such as a randomized multicentre study on the long-term effects of GFD with particular attention to the imbalance in daily fat intake.


Sujet(s)
Maladie coeliaque/diétothérapie , Régime sans gluten , Matières grasses alimentaires/administration et posologie , Ration calorique , Adolescent , Enfant , Femelle , Humains , Mâle
6.
Arch Dis Child Fetal Neonatal Ed ; 93(2): F135-9, 2008 Mar.
Article de Anglais | MEDLINE | ID: mdl-18006568

RÉSUMÉ

OBJECTIVES: To compare the accuracy of a new transcutaneous bilirubinometer, BiliMed (Medick SA, Paris, France) with BiliCheck (Respironics, Marietta, GA, USA), a widely available instrument, and with total serum bilirubin measurement. DESIGN: A prospective double-blind study comparing the two devices was carried out. 686 healthy newborns needing measurement of their bilirubin were enrolled over a 4-month period. Serum and transcutaneous bilirubin measurements were taken with both devices within 15 minutes. The order of use of the instruments was randomised. SETTING: Well-baby nursery ward in a university hospital, tertiary referral centre. RESULTS: The linear regression analysis showed a better correlation between BiliCheck and serum bilirubin (r = 0.75) than between BiliMed and serum bilirubin (r = 0.45). BiliCheck variability (+/-2 SD of the mean bias from serum bilirubin) was within -87.2 to 63.3 micromol/l, while BiliMed variability was within -97.5 to 121.4 micromol/l. The receiver operating characteristic analysis (for serum bilirubin levels >205.2 micromol/l or >239.4 micromol/l) showed significantly higher areas under the curve for BiliCheck than those for BiliMed (p<0.001). CONCLUSIONS: Despite the potential practical advantages of BiliMed, its reduced diagnostic accuracy in comparison with BiliCheck does not justify its use in clinical practice.


Sujet(s)
Bilirubine/sang , Méthode en double aveugle , Femelle , Humains , Nouveau-né , Ictère néonatal/diagnostic , Lumière , Mâle , Dépistage néonatal , Valeur prédictive des tests , Grossesse , Études prospectives , Reproductibilité des résultats , Analyse spectrale/instrumentation , Analyse spectrale/méthodes , Résultat thérapeutique
7.
Minerva Pediatr ; 59(3): 183-9, 2007 Jun.
Article de Italien | MEDLINE | ID: mdl-17519862

RÉSUMÉ

AIM: The aim of this paper was to assess the ability of total serum bilirubin (TSB) levels in the first 3 days of life to predict subsequent nonphysiologic hyperbilirubinemia. METHODS: The predictive ability of an hour-specific nomogram for TSB values in the first week of life was prospectively assessed in 1496 full term neonates admitted to a first level neonatal unit, using a single TSB value or two consecutive ones, when available. RESULTS: The incidence of TSB values > 12 mg/dL was 9.6%, while the incidence of TSB > 15 mg/dL was 2.6%. A sensitivity of 97.9% and a negative predictive value (NPV) of 99.6% were obtained with a single bilirubin determination applying Trend 12, while 82.5% of sensitivity and 99.4% of NPV were obtained with Trend 15. Two consecutive TSB determinations identified all infants reaching TSB values > 12 mg/dL and all neonates but 5 reaching TSB values > 15 mg/dL (92.1% of sensitivity and 99% of NPV) CONCLUSION: The hour-specific TSB determination in the first 3 days of life is able to predict all neonates at risk of nonphysiologic hyperbilirubinemia and could facilitate a safe discharge from the hospital and a targeted intervention and follow-up.


Sujet(s)
Bilirubine/sang , Hyperbilirubinémie néonatale/sang , Marqueurs biologiques/sang , Femelle , Humains , Hyperbilirubinémie néonatale/diagnostic , Nouveau-né , Ictère néonatal/sang , Ictère nucléaire/sang , Mâle , Dépistage néonatal , Nomogrammes , Valeur prédictive des tests , Études prospectives , Reproductibilité des résultats , Appréciation des risques , Facteurs de risque , Sensibilité et spécificité , Statistique non paramétrique
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