Scintillators, materials that produce light pulses upon interaction with ionizing radiation, are widely employed in radiation detectors. In advanced medical-imaging technologies, fast scintillators ...enabling a time resolution of tens of picoseconds are required to achieve high-resolution imaging at the millimetre length scale. Here we demonstrate that composite materials based on fluorescent metal–organic framework (MOF) nanocrystals can work as fast scintillators. We present a prototype scintillator fabricated by embedding MOF nanocrystals in a polymer. The MOF comprises zirconium oxo-hydroxy clusters, high-Z linking nodes interacting with the ionizing radiation, arranged in an orderly fashion at a nanometric distance from 9,10-diphenylanthracene ligand emitters. Their incorporation in the framework enables fast sensitization of the ligand fluorescence, thus avoiding issues typically arising from the intimate mixing of complementary elements. This proof-of-concept prototype device shows an ultrafast scintillation rise time of ~50 ps, thus supporting the development of new scintillators based on engineered fluorescent MOF nanocrystals.Composites of fluorescent metal–organic framework nanocrystals in a polymer are exploited to create fast scintillators with a rise time of about 50 ps.
A new inorganic scintillation material based on Ba-Gd silica glass doped with cerium (BGS) is fabricated and studied. With the highest light yield among heavy glasses at the level of 2500 ph/MeV and ...fast scintillation response, the new scintillator ensures a good coincidence time resolution of < 230 ps FWHM for 511 keV γ-quanta from a 22Na source and SiPM readout. In addition to good performance in γ-quanta detection, the material demonstrates capability for efficient detection of low-energetic neutrons. The scintillator is produced by exploiting the standard industrial glass technology, which allows for an unlimited scaling up the conversion of raw material into a high-quality scintillator at a high rate. The glass can be casted in application-specific molds, so minimizing the material losses. The presented glass scintillator has potential for further improvement of its light output and scintillation response time.
Metasurfaces and, in particular, metalenses have attracted large interest and enabled various applications in the near-infrared and THz regions of the spectrum. However, the metalens design in the ...visible range stays quite challenging due to the smaller nanostructuring scale and the limited choice of lossless CMOS-compatible materials. We develop a simple yet efficient design of a polarization-independent, broadband metalens suitable for many CMOS-compatible fabrication techniques and materials and implement it for the visible spectral range using niobium pentoxide (Nb2O5). The produced metalens demonstrates high transmittance and focusing ability as well as a large depth of focus, which makes it a promising solution for a new generation of silicon photomultiplier photodetectors with reduced fill factor impact on the performance and reduced electron–hole generation regions, which altogether potentially leads to improved photodetection efficiency and other characteristics.
Background
Evidence links sedentary behaviours (SB) with poorer health outcomes; i.e. higher screen time is associated with poorer fitness and cardiometabolic health, as well as unfavourable measures ...of adiposity, mental health and social behaviour in children. The WHO guidelines for children recommend reaching at least an average of 60 min per day of physical activity (PA). Several studies show a correlation between parental education (PE) and children PA levels. This study aims to analyse the influence that PE has on childrens' sedentary lifestyle and PA habits in Italian society.
Methods
We conducted a cross-sectional analysis among 428 children aged 6-11 recruited in a primary school of Calderara di Reno (Italy) in 2017. Children's and parents' information were collected at baseline (i.e. age, BMI, occupation, instruction). PA level and SB were evaluated using a weekly diary investigating screen time (PC and TV), sports practice and active play (i.e: running, jumping, riding a bike, etc.). We investigated the relationship between lifestyles and PE (high school degree or lower vs college degree or higher) through multiple linear regression models adjusted for age and gender.
Results
Our models show that fathers' educational level is not related to children's SB. PA habits and weekly sports activities are not related to PE. On the other hand, higher mothers' educational level shows to be linked to a decreased TV screen time (p = 0.003) and time spent using a computer (p = 0.035). Notably, older children spend more time using PCs or devices (p = 0.001), net of confounding variables.
Conclusions
Our findings show that mothers' educational level positively influences children's lifestyle. This result might be related to the fact that, in the Italian context, mothers are usually the principal children's caregiver influencing their daily routine. In light of this, mothers might be considered a primary target when implementing public health interventions to reduce children's SB.
Key messages
Higher mothers’ educational level is positively associated with healthier lifestyles in children, in particular in determining a less sedentary behaviour.
Fathers' degree of education does not display any impact on children's attitude toward sports and PA.
A spaghetti calorimeter (SPACAL) prototype with scintillating crystal fibres was assembled and tested with electron beams of energy from 1 to 5 GeV. The prototype comprised radiation-hard ...Cerium-doped Gd3Al2Ga3O12 (GAGG:Ce) and Y3Al5O12 (YAG:Ce) embedded in a pure tungsten absorber. The energy resolution was studied as a function of the incidence angle of the beam and found to be of the order of 10%/E⊕1%, in line with the LHCb Shashlik technology. The time resolution was measured with metal channel dynode photomultipliers placed in contact with the fibres or coupled via a light guide, additionally testing an optical tape to glue the components. Time resolution of a few tens of picosecond was achieved for all the energies reaching down to (18.5 ± 0.2) ps at 5 GeV.
The sensitivity of blood cultures for diagnosing invasive candidiasis (IC) is poor. We performed a validated Candida real-time polymerase chain reaction (PCR) and the Fungitell 1,3-β-D-glucan (BDG) ...assay on blood samples collected from prospectively identified patients with IC (n = 55) and hospitalized controls (n = 73). Patients with IC had candidemia (n = 17), deep-seated candidiasis (n = 33), or both (n = 5). Controls had mucosal candidiasis (n = 5), Candida colonization (n = 48), or no known Candida colonization (n = 20). PCR using plasma or sera was more sensitive than whole blood for diagnosing IC (P = .008). Plasma or sera PCR was more sensitive than BDG in diagnosing IC (80% vs 56%; P = .03), with comparable specificity (70% vs 73%; P = .31). The tests were similar in diagnosing candidemia (59% vs 68%; P = .77), but PCR was more sensitive for deep-seated candidiasis (89% vs 53%; P = .004). PCR and BDG were more sensitive than blood cultures among patients with deep-seated candidiasis (88% and 62% vs 17%; P = .0005 and .003, respectively). PCR and culture identified the same Candida species in 82% of patients. The sensitivity of blood cultures combined with PCR or BDG among patients with IC was 98% and 79%, respectively. Candida PCR and, to a lesser extent, BDG testing significantly enhanced the ability of blood cultures to diagnose IC.
Particle physics experiments running at future accelerator facilities will rely on fast timing detectors to cope with high event pileup and to enhance particle identification capabilities. Direct ...band gap engineered semiconductor nanostructures show a high potential for emission of prompt photons due to quantum confinement, standing out in fast timing and high light yield with potential low cost production, thus triggering interest in the high energy physics community. In this contribution, characterization results of the scintillation properties of some promising nanomaterial scintillators will be presented and an overview of possible light-based detector designs based on these nanomaterials will be given, focusing on the NanoCal Blue Sky project of the European project AIDAinnova, a new generation of shashlik calorimeters. First results, obtained during test beam activities, will be presented as well.
The tail is characterized in two sympatric species of endemic saurians from Ecuador. We used glue traps in eight transects of 500 m distance and fall traps of 80x80x80 cm. The condition tails intact, ...absent, and regenerated were studied. Between 2012 and 2014 we captured 138 individuals, 125 individuals belong to Stenocercus guentheri and thirteen to Pholidobolus montium. About 61% of the individuals had an intact tail. For the first time, we reported tail bifurcation in Stenocercus guentheri three cases were observed with this condition.
Se caracteriza la cola en dos especies simpátricas de saurios endémicos de Ecuador. Utilizamos como técnicas de muestreo trampas de goma en ocho transectos de 500 m de distancia y trampas de caída de 80×80×80 cm. Para evaluar la condición de las colas se establecieron las categorías: intacta, ausente y regenerada. Entre 2012 y 2014 capturamos 138 saurios, 125 individuos de Stenocercus guentheri y trece de Pholidobolus montium. Alrededor del 61% de los individuos tenían la cola intacta. Reportamos por primera vez bifurcación de la cola en Stenocercus guentheri observamos tres individuos con esta característica.
T-cell depletion (TCD) of allogeneic stem cells transplantation (HSCT) is the most powerful approach to overcome HLA barriers in patients with high risk malignancies, lacking a conventional donor. ...However, the prolonged immune deficiency resulting from TCD significantly impairs the outcome of HSCT from a haploidentical family donor (haplo-HSCT). In a phase I-II clinical trial (protocol MMTK007), we showed that the add-back of suicide-gene transduced donor lymphocytes (TK+ cells) provides early immune-reconstitution (IR), crucial to avoid opportunistic infections and disease relapse. While the achievement of an early and sustained IR significantly reduced the incidence of infectious complications and mortality, the kinetic of abatement of viral reactivations differed in different patients, suggesting variability in the repertoire, function and persistence of viral-specific T cells. To gain insights on the activity of the post-transplant immune system, we focused on immune responses to cytomegalovirus (CMV) and Ebstein Barr virus (EBV) as clinical paradigm of an effective immune system. In our trial 29 patients (median age 52y) were transplanted for high-risk leukemia. Seventeen pts received TK-DLI starting at day +42, 14 pts obtained prompt immune reconstitution with CD3+ >100/mcl at day +86 (median) from SCT and day +21 from TK-DLI. Twelve/14 experienced CMV reactivation, 3 reactivation/patient (median), each reactivation required 14 days (median) of pre-emptive treatment with foscarnet to achieve a complete clearance; in 2/38 events, a CMV antigenemia persistent during foscarnet treatment was cleared by ganciclovir administration. In this series, the last CMV reactivation requiring pre-emptive treatment happened at day +84 from SCT and day +19 from TK-DLI. Nine/14 experienced EBV reactivation, 1 reactivation/patient (median), 6 patients required treatment with rituximab (375 mg/mq weekly) for 3 cycles (median). In 3 cases we documented EBV lymphoproliferative disease, that were completely controlled with the treatment. The proportion of lymphocytes committed to produce IFN-γ upon CMV or EBV stimulation normalized within the first 3 months post transplant. The analysis of CMV and EBV T-cell response showed a prevalent host-restriction pattern, suggesting active modulation of the T-cell repertoire by the host environment. The TCR-Vβ repertoire progressively changed from oligoclonal into polyclonal and normalized by 1 year after transplant. The progressive acquirement of a protective, host-restricted, anti-viral response, highly correlated with a decline in the occurrence of any infectious event, that were nearly abrogated by 6th month post transplant. The overall cumulative infectious mortality beyond day +100 post transplant was 12,5% in TK treated patients demonstrating the efficacy of this strategy in building a protective immune system.
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