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Theoretical calculations are proving as an essential tool to understand luminescence processes even for systems including lanthanide (Ln3+) ions. As such, the aim of this study is that of presenting a general and comprehensive theoretical protocol based on DFT calculations to rationalize and possibly drive the design of new luminescent Ln3+ complexes through the ab initio determination of the electronic properties of a ligand and two Eu3+ complexes. Different theoretical methodologies have been combined to look into the excited state energies, the luminescence quantum yield, and the energy transfer processes. The protocol has been validated for a β-diketone ligand and two Eu3+ complexes, which contain, in addition to the main ligand, ethanol or triphenylphosphine oxide. Moreover, by starting from the geometry optimization up to the estimation of the ligands’ singlet and triplet lowest energy states, theoretical results quantitatively agree with luminescence experimental parameters, providing at the same time insights into the different energy transfer processes. The different quantum yields of the two complexes have been correctly reproduced.

The ability to tune and enhance the properties of luminescent materials (phosphors) is essential for optimizing the performance of devices and understanding the luminescence mechanisms. Eu3+ was used as a local structural probe for studying the impact of ferroelectric order and, more generally, of polar order on the photoluminescence of the model BaZrxTi1-xO3 perovskite (x = 0-1). The polar order evolves from long-range order typical of classic ferroelectrics (x = 0-0.15), via a diffuse transition behaviour (x = 0.15-0.25), to short-range order typical of relaxors (x >= 0.25) until the paraelectric state of BaZrO3 is achieved. The cooperative polar interactions existing in the lattice (x < 1) promote the off-centre displacement of Eu3+ determining a change of the lanthanide site symmetry and, consequently, an abrupt variation of the photoluminescence emission with temperature.

Risultati conseguiti nel 2019 e previsione attività nel 2020 che riguardano sia l'aspetto metodologico che quello applicativo inerenti l'utilizzo delle Temperature Sensitive Paint (TSP) nello studio dei flussi a parete.

Phthalates and bisphenol A (BPA), plasticizers used in several products of daily life, are considered as endocrine disrupters, therefore children exposure is particularly relevant. The LIFE PERSUADED project aims to define the following: (a) the evaluation of internal levels of DEHP's metabolites and BPA in Italian children and their mothers, (b) the association of the exposure with puberty development and obesity diseases, and (c) the effects of exposure in juvenile in vivo model. The cross-sectional study has involved 2160 mother-child pairs, including males and females, children and adolescents, from urban and rural areas of North, Center, and South Italy. A structured questionnaire and a food diary are designed to evaluate the association between lifestyle variables potentially related to DEHP/BPA exposure and internal levels, through univariate and multivariate analyses. Two pilot case-control studies are carried out on idiopathic premature thelarche and precocious puberty (30 girls each group, aged 2-7 years) and idiopathic obesity (30 boys and 30 girls, aged 6-10 years), matched to healthy controls. BPA and DEHP's metabolites are analyzed in urine samples from all recruited subjects. Clinical and toxicological biomarkers are evaluated in serum of case-control subjects. Moreover, the toxicity study is carried out in a juvenile rodent model exposed to mixtures of BPA and DEHP at dose levels recorded in children population. The scientific results of LIFE PERSUADED will contribute to risk assessment of BPA and DEHP.

BaZrxTi1-xO3 (BZT) solid solutions with perovskite structure show a series of phase transitions and a progressive evolution of ferroelectric order, from long-range typical of ferroelectrics....

BaTiO3-based ferroelectric ceramics show interesting properties such as high dielectric constant, low losses, high hydrostatic piezoelectric coefficient and PTCR effect. For these reasons, barium titanate is widely used in the electronic industry for manufacturing miniaturised multilayer ceramic capacitors, underwater transducers and self-regulating thermistors. BaZrxTi1-xO3 (BZT) solid solution possesses the perovskite structure and shows a series of phase transitions and a progressive evolution of ferroelectric order, from long-range order typical of classic ferroelectrics (x = 0-0.15), via a diffuse transition behaviour (x = 0.15-0.25), to short-range order typical of relaxors (x >= 0.25) and finally paraelectric non polar state for neat BaZrO3. The trivalent europium ion (Eu3+) is well known for its strong luminescence in the red spectral region. Even very small variations in the coordination sphere of europium ions induce major changes in the emission spectrum. Thanks to these features, Eu3+ is a unique and powerful local structural probe. In this framework, we have investigated the photoluminescence (PL) emission of dense BZT ceramics doped with Eu3+ at the Ba site with composition EuyBa1-yZrxTi1-x-y/4O3 (y = 0.01, x = 0, 0.05, 0.15, 0.30, 0.50, 0.70, 1) in the temperature range -100 to 140 °C. The ceramics were prepared by the classical solid-state route and sintered at 1450-1550 °C. The dielectric permittivity of the samples was measured from -150 to 150 °C at 10e2-10e6 Hz to determine reference values of the phase transition temperatures and the type of polar order. The PL bands revealed significant shape and intensity variations which can be correlated with the existence and nature (long-range or short-range) of polar order rather than the phase transitions. The spectral features observed for compositions with long-range ferroelectric order (x = 0-0.15) support the off-centre displacement of the Eu3+ ion with respect to the lattice position occupied by barium.

In the field of environmental remediation strategies, multifunctional materials able to act both for fast pollutants adsorption and degradation under visible light are highly desirable. In this framework, bismuth oxyhalogenides (BimOnXo, X= Cl, Br, I), and (BiO)2CO3 nanostructures represent an interesting solution owing to their peculiar physico-chemical properties, layered structures, morphologies and low toxicity. Besides single phase materials, composite systems that display heterojunction structures, e.g. BiOCl/Bi2O3, BiOCl/BiOI, BiOI/Bi12O17Cl2, can operate far better thanks to the presence of synergic effects at the interface between the two components. The present study explores the modulation of chemico-physical properties, adsorption capacity and photodegradation activity towards model pollutants, i.e. Rhodamine B (RhB) and Methyl Orange (MO), of Bi12O17Cl2/(BiO)2CO3 nanocomposite materials, by tailoring the relative amount of the two components through different post-synthe sis treatments with UV-light or thermal annealing. In this regard, Bi12O17Cl2 is used as sensitizer to harvest the visible light being coupled to (BiO)2CO3 which has almost no visible absorption. The obtained results evidenced the ability of the employed strategy to modulate morphology, surface areas, ?-potential, optical absorption in the visible range and dye adsorption/degradation properties. The best performance was achieved by (BiO)2CO3-rich samples which adsorbed 80% of MO within 10 minutes contact time and decomposed the remaining 20% by visible light photocatalysis. Bi12O17Cl2-rich composite materials displayed a lower adsorption ability, but thanks to the stronger absorption in the visible they behaved as more effective photocatalysts.

BaTiO3-based ferroelectric ceramics show interesting properties such as high dielectric constant, low losses, high hydrostatic piezoelectric coefficient and PTCR effect. For these reasons, barium titanate is widely used in the electronic industry for manufacturing miniaturized multilayer ceramic capacitors, underwater transducers and self-regulating thermistors. BaZrxTi1-xO3 (BZT) solid solution shows a series of phase transitions and a progressive evolution of ferroelectric order, from long-range order typical of classic ferroelectrics (x = 0) to short-range order typical of relaxors (x >= 0.25), which consequently affects the functional properties. This material can be considered as a model system for understanding the composition-property correlations in ferroelectric ceramics. The trivalent europium ion (Eu3+) is well known for its strong luminescence in the red spectral region. Even very small variations in the coordination sphere of europium ions induce major changes in the emission spectrum. Thanks to these features, Eu3+ is a unique and powerful local structural probe. In this framework, we used photoluminescence (PL) as a tool to investigate the phase transitions and the ferroelectric order in BZT using Eu3+ as active centre. Dense ceramics (relative density: 96-99%) with composition EuyBa1-yZrxTi1-x-y/4O3 (y = 0.01, x = 0, 0.05, 0.15, 0.30, 0.50, 0.70, 1) were prepared by the classical solid-state route and sintered at 1450-1500 °C. The dielectric permittivity of the samples was measured from -150 to 150 °C and at 102-106 Hz to determine reference values of the phase transition temperatures. The study of PL spectra as a function of temperature, in the interval -100 to 140 °C, revealed strong shape and intensity variations of the emission bands in the proximity of phase transitions as well as a significant dependence of the band intensity on x in the composition region (x >= 0.30) corresponding to the relaxor behaviour.

Background We conducted a study to evaluate efficacy and safety of dimeticone 4%, a lotion with no conventional insecticide activity, to cure lice infection and to prevent spread of infestation/reinfestation by prophylaxis of classmates. Methods: The study is carried out between April 2008 and June 2008 in Petranova International Institute in Rome. A total of 131 children, aged 3 to 13 years (median age: 7 years) were included in the study. All participants received treatment with dimeticone 4% that was applied both to children with the infestation, to cure it, and to all classmates, to prevent the spreading of the infestation. They have been controlled after 7 and 30 days from the application of dimeticone. Results: At baseline we found a positivity of lice infestation in 23/131 children (17.6%), whereas 108/131 (82.4%) children were free from lice. After 7 days of treatment with dimeticone 4%, 7/23 (30.4%) positive children still had lice infestation, with a cure rate of 69.6% (16/23). At 30 days 26/131 children (19.9%) were infested: 15 children were lice free at baseline whereas 11 had lice at both evaluations; the cure rate amounted to 52.2% (12/23). The reinfestation rate (percentage of positive children that showed negativity at baseline) was 5.3% (7/131) at 7 days and 11.5% (15/131) at 30 days. Conclusion: The lower reinfestation rate showed in our trial suggests that this approach could be effective in reducing spreading of head lice in small communities. More studies are needed to confirm our findings.

Background To evaluate physical and mental health in children in foster care and comparison with general population. Methods: The study is carried out between September 2011 and April 2012 into nine group homes in Rome. It involved 112 children ranging in age 2–17 years, living in temporary care facilities or institutes. All data came out of clinical history and physical exams, validated by a pediatrician. Such data were being then compared with samples of general population. Results: Significant themes were high percentage of children with psychiatric disorders in foster care (22.3%); high percentage of psychiatric disorders diagnosed immediately while arriving at the foster care (56%); no significant differences in weight, height and BMI between children in foster care and general population; significant differences (P

BaTiO3-based ferroelectric ceramics show interesting properties such as high dielectric constant, low losses, high hydrostatic piezoelectric coefficient and positive coefficient of resistivity. For these reasons, barium titanate is widely used in the electronic industry for manufacturing miniaturized multilayer ceramic capacitors, underwater transducers and self-regulating thermistors. BaZrxTi1-xO3 (BZT) solid solution shows a series of phase transitions (PT) and a progressive evolution of ferroelectric order, from long-range order typical of classic ferroelectrics (y = 0) to short-range order typical of relaxors (x >= 0.25), which consequently affects the functional properties. This material can be considered as a model system for understanding the composition-property correlations in ferroelectric ceramics. The trivalent europium ion (Eu3+) is well known for its strong luminescence in the red spectral region. Even very small variations in the coordination sphere of europium ions induce major changes in the emission spectrum. Thanks to these features, Eu3+ is a unique and powerful local structural probe. In this framework, we used photoluminescence (PL) as a tool to investigate phase transitions and the ferroelectric order in BZT using Eu3+ as active centre. Dense ceramics (relative density: 96-99%) with composition EuxBa1-xZryTi1-y-x/4O3 (x = 0.01, y = 0, 0.05, 0.15 and 0.30) were prepared by the classical solid-state route and sintered at 1450-1500 °C. The dielectric permittivity of the samples was measured from -150 to 150 °C and at 102-106 Hz to determine reference values of the phase transition temperatures. The study of PL spectra as function of the temperature, in the interval -100/140 °C, revealed strong shape variations in the PT proximity thus allowing the identification of the stability range of the different crystalline phases.

Background The pandemic influenza A/H1N1, spread through the world in 2009, producing a serious epidemic in Italy. Complications are generally limited to patients at the extremes of age (65 years) and those with comorbid medical illness. The most frequent complications of influenza involve the respiratory system. Case Presentation A 3-year-old boy with a recent history of upper respiratory tract infection developed a nephrotic syndrome. Together with prednisone, furosemide and albumin bolus, a therapy with oseltamivir was started since the nasopharyngeal swab resulted positive for influenza A/H1N1. Clinical conditions and laboratory findings progressively improved during hospitalization, becoming normal during a 2 month follow up. Conclusion The possibility of a renal involvement after influenza A/H1N1 infection should be considered.

Background: We carried out a study of the antibody pattern in 50 celiac children [34 females (F) and 16 males (M); F/M, 2.1], ages 7 months-15 years, compared with that in 25 control subjects (13 females and 12 males) of the same age. Methods: IgA and IgG antigliadin antibodies (AGA) were determined with an enzyme-linked immunosorbent assay technique. IgA anti-R1-reticulin antibodies (ARA) and IgA antiendomysium antibodies (EmA) were determined with the fluorescein isothiocyanate-conjugate-labeled antihuman immunoglobulin technique. To compare sensitivity and specificity, EmA were identified using monkey esophagus and human umbilical cord as substrates. Results: While AGA (IgA and IgG) showed a high sensitivity but a low specificity, ARA showed a high specificity but a low sensitivity. Data on EmA showed a high sensitivity and specificity with both tissue sections, with monkey esophagus being more sensitive (96%) and umbilical cord more specific (100%). Conclusions: Our results confirm the importance of celiac disease-related antibodies in identifying celiac children. Moreover, the easy availability of human umbilical cord indicates that it would be proper to use this tissue as substrate, instead of monkey esophagus, for EmA search in the future.

The association between Down's syndrome (DS) and celiac disease (CD) has been confirmed by several authors. The sensitivity and specificity of antigliadin antibodies (AGAs), the clinical features of subjects with DS and CD (DS-CD+), the incidence of CD, and the results of serological and molecular class I and II HLA typing were determined in a sample of 57 Sicilian subjects with DS. Six (10.5%) and 17 subjects (29.8%) showed high levels of IgA AGAs and IgG AGAs, respectively. AGAs sensitivity and specificity were lower than in the population without DS. Ten people with DS were submitted to jejunal biopsy, and seven (12.2%) showed CD according to ESPGAN criteria. All seven patients were put on gluten-free diet, followed by rapid disappearance of symptoms. Class I and II HLA serological and molecular typing was carried out in seven DS-CD + subjects, 22 people with DS without CD (DS-CD-), five subjects with CD without DS, and 20 controls. Between DS-CD + and DS-CD- subjects, no statistically significant difference regarding serum HLA class I antigens was found. DQA1*0101 allele appears significantly in DS-CD + patients and deserves to be searched for in a larger sample to assess its meaning in the DS-CD association.

The etiology of idiopathic scoliosis (IS) has been the subject of extensive research, and the current opinion is in favor of a multifactorial pathogenesis with an important genetic component. The aim of this study is to investigate the pattern of inheritance over generations of IS and its possible risk factors.A total of 70 patients affected by IS was selected and studied up to the third generation for an overall cohort of 2,055 subjects. The genealogy was investigated and correlated for scoliosis.The outcomes showed that 73 % of the patients had an age between 12 and 15 years. The 60 % of the mothers had an age between 20 and 29 years and 57 % of the patients were "first born". The 5.8 % of the brothers and the 12.7 % of the sisters were affected by scoliosis. From the analysis of the total sample, it is clear that in 53 % of the families, there is at least another scoliotic besides the patient.The statistical analysis revealed three different types of transmission: autosomic dominant, autosomic recessive and multifactorial. When this last mode of inheritance is involved, female sex and firstborn resulted as risk factors of IS.

ACTA PAEDIATR SUPPL

The preparation of sol-gel glasses is described wherein highly stable Eu(III) centres are anchored to the silica glass upon acidic hydrolysis and by using tetraethylorthosilicate (TEOS) as a silica source. The complex employed is Eu?1 and is obtained from bipartite ligand 1, which features a DO3A macrocycle as a hosting unit for the Eu(III) centre, a methoxy-acetophenone unit as an antenna chromophore, and an alkyl chain bearing one primary hydroxy group (DO3A is 1,4,7,10- tetraazacyclododecane-1,4,7-triacetic acid). Eu?1 is linked to the forming silica glass through the -OH groups and a uniform distribution of the luminescent centres is obtained, as indicated by results from secondary ion mass spectrometry in-depth profiling. The luminescent efficiency of the Eu(III) centres in the solid matrix is evaluated to be 10%, which is comparable to that of Eu?1 in water solution and of a convenient reference complex, Eu?2 (2 is a ligand featuring the same hosting and antenna functionalities of 1, wherein the -OH residue is replaced by an unreactive group, a benzoylmethyl residue). A discussion is given of the photophysical properties exhibited by the complexes in the film and in solution.